Oct 24

PowerHA and LVLT4i.

We have had a number of conversations about LVLT4i and what it offers to the Managed Service Provider(MSP). As part of those discussions the IBM solution PowerHA often comes up as it also uses iASP technology but that is really where the similarity ends.

PowerHA uses the iASP to isolate the objects that are to be replicated to another system/storage device and it has an exact copy of the iASP from the source on the target. Changes are captured at the hardware level and are sent to the remote system as they occur.

LVLT4i only replicates objects to a remote iASP, it uses either Audit journal triggers or the Remote Journal technology to capture and send the data. The source object resides in *SYSBAS and the target object in an iASP, it is used primarily to allow multiple copies of the same library/object combination to be stored on a single system. The remote iASP is always available to the user.

iASP is not widely implemented at customer sites, this is in part due to the lack of support for iASP’s built into many of the applications that run on the IBM i today (many of the applications were built before iASP technology was available). For a customer to migrate an application to allow iASP use there are a number of constraints which have to be considered plus each users environment has to be adjusted to allow the iASP content to be used (SETASPGRP etc). This has further limited the use of iASP as many do not feel the benefits of moving to the iASP model out-weight the cost of migration. Another issue is you are now adding an additional storage management requirement, the iASP is disk based which will require protection to be added in some form. With LVLT4i you can leave your system unchanged, only the target system is going to need iASP setup and that will be in the hands of your Managed Service Provider. The decision about what to replicate is yours, with some professional help from a Managed Service Provider who knows your application it should be pretty bullet proof when it comes to recovery.

If you implement PowerHA you are probably going to need to set up an Admin Domain, this is where any *SYSBAS objects such as system values, profiles and configuration objects are managed. in LVLT4i we do not manage system values or configuration objects (configuration objects can be troublesome especially with TCP/IP) or system values. We have however just built in a new profile and password process to allow the security aspects of an application to be managed across systems in real time. Simple scripts can capture configuration and system value settings many of which are not important to your application so LVLT4i has you covered. If we find a need to build in system value or configuration management we will do so fairly rapidly.

PowerHA is priced by Core, so you license it for each Active Core on each system. Using CBU licensing, PowerHA can utilize lower active cores on the target and only activate them when the system is required. Unfortunately in a HA environment you are probably switching regularly so you will have the same number of active cores all the time. LVLT4i is priced by IBM tier regardless of the number of active cores. The target system license is included with the source system license regardless of the target system tier so a Manage Service Provider who has a P30 to support many P05 clients is not penalized.
PowerHA also comes in a few flavors which are decided on by the type of set up you require. Some of the functionality such as Asynchronous mirroring is only available in the Enterprise edition so if you need to ensure your application is not constrained by remote confirmation processing (waiting for the remote system to confirm it has the data) your are going to need the Enterprise edition which costs more per core. LVLT4i comes in one flavor and is based on a rental model, the transport of data over Synchronous/Asynchronous remote journals is available to all plus it supports any geographic model.

Because the iASP is always available the ability to backup at any time is possible with LVLT4i. With PowerHA you have to use a Flashcopy to make another disk based copy of the iASP which can then be used for the back up to tape etc. That requires a duplicate set of disks to match the iASP content. With LVLT4i you can use Save While Active or suspend the apply process for point in time saves, the remote journal will still be receiving your application updates which can be applied once the save has completed so data protection is not exposed.

RPO is an important number which is regularly banded around by the High Availability providers, PowerHA states it is 0 because everything is replicated at the hardware level. We believe LVLT4i is pretty close to the same but there are a couple of things to consider.

First of all, RPO of 0 will require synchronous delivery of changes, if you use an Asynchronous delivery method queued changes will affect that for either solution. LVLT4i uses Remote journalling for data changes, so if you use Synchronous mode I feel the two are similar in effect.

Because we use a different process for object changes, any object updates are going to be dependent on the level of change activity being processed by the object replication processes. The amount of data being replicated is also a factor as a single stream of object changes is used to transfer the updates. We have done a lot of work on minimizing the data which has be be sent over the wire such as using commands instead of save restore, pipe-lining changes so multiple updates to an object are optimized into a single action and compression within the save process. This has greatly reduced the activity and therefore bandwidth requirements.

PowerHA is probably better at object replication because of the technology IBM can access, plus it is going to be carried out in line with the data changes. The same constraints about using synchronous mode affect the object replication process so bandwidth is going to be a major factor in the speed of replication etc. Having said that, most of the smaller clients we have implemented any kind of availability for (HA4i/DR4i) do not see significant object activity and little to no backlogs in the object replication process.

The next recovery figure RTO talks about how long it will take from making the decision to switch, to actually switching. My initial findings about iASP tended to show a fairly long role-swap time because you had to vary off the iASP and then on again to make it available. We have never purchased PowerHA so our tests are based around how long it took to vary off and then on again a single iASP on our P05 system (approximately 20 minutes). I would suspect the newer and faster systems have reduced the time it takes but it is still a fairly long time. LVLT4i is not a contender in this role because we expect the role-swap times to be pretty extended (4 – 12 hours) even if you do a lot of automation and preparation.

One of the issues which affect all High Availability Solutions is the management of batch, if you have a batch process running at the time of failure it could affect the integrity of the application data on the target system. LVLT4i and PowerHA both have this limitation as the capture of job queue content is not possible even in an iASP, but we have a solution which when integrated with LVLT4i will allow you to reload job queues and identify orphaned data which has been applied by a batch process. Our JQG4i product captures all activity for specific job queues and will track each job from load to completion. This will allow you to recover the entire application environment to a known start point and thereby ensure your data integrity is maintained. Just being able to automatically reload jobs that did not run before the system failure is a big advantage that many current users benefit from.

There are plenty of options out there to choose from but each has its own strengths and weaknesses. LVLT4i uses the same replication technology as out HA4i and DR4i products with enhancements to allow the use of iASP as the target disk. It is not designed to meet the same RTO expectations as PowerHA even though both make effective use of iASP technology. However, PowerHA is not necessarily the best option for everyone because it does have a number of dependencies that make it more difficult/costly to implement than a logical replication solution, you have to weigh up the pros and cons of each technology and make a decision about what is important.

If you are interested in knowing more or would like to see a demo of the LVLT4i product please let us know and we will be happy to schedule.


Oct 23


We are looking at how to manage the recovery of profiles and passwords in an environment where the profiles cannot be managed constantly. When using our HA4i product we have the ability to constantly maintain the user profiles and passwords because the user profiles are allowed to exist on the target system. However in an environment such as that required for the LVLT4i product User Profiles cannot exist because they may conflict with other profiles from other clients (All user profiles have to exist in *SYSBAS)

The process we have tested involves using the SAVSECDTA command to save the data to a save file, this save file can be automatically replicated to the iASP on the target system. The Profile information is captured in a file which is also replicated to the target iASP using normal replication processes (Remote Journals). When the system needs to be rebuilt for recovery the information collected in the SAVSECDTA file will be restored, the profiles will be updated using the profile data we have collected and then the RSTAUT command will be run. This will bring the system and profiles up to the latest content available.

While we were testing the processes we noticed a very strange thing. The first time we ran the request on a system it took a little while to complete about 1 minute, but when we ran the request again it took only a couple of seconds? The content of the save file was the same (we even set the compression level to high with no significant impact) but why is it taking so long the first time? We thought that maybe it was because the save file was already available (we put it in QTEMP) but again signing off and on then retrying gave us the same results, it now only took a few seconds to complete the save? Signing onto another system and doing the exact same process yielded the same results, the first time took about 1 minute while subsequent tries only took a few seconds.

We do not know what is going on under the covers but it certainly seems like something gets lined up after the first save, this leads us to believe that doing a SAVSECDTA on a regular basis (nightly?) may not be a bad thing. If you have any information as to why, let us know as we are very curious.

LVLT4i is new and while we feel the product should attract a number of Managed Service Providers we are interested in knowing what you think. Would you be interested in a solution that provides a very low RPO (close to zero data loss) with a RTO in the 4 – 12 hours time frame? If you are interested let us know, we will be happy to put you in touch with one of the MSP’s we have been working with. If you are a MSP and would like to know more or even see a demo of the product let us know as well, we are excited by the opportunities this could bring.


Oct 20

New Product Library Vault, Why?

We have just announced the availability of a new product, Library Vault for IBM i (LVLT4i) which is aimed primarily at the Managed Service Providers. The product allows the replication of data and objects from *SYSBAS on a clients system to an iASP on a target system.

The product evolved after a number of discussions with Managed Service Providers who were looking for something less than a full blown High Availability Product but more than a simple Disaster Recovery solution. It had to be flexible enough to be licensed by the replication content not the systems being used to run it on.

We looked at our existing products and how the licensing worked, it became very apparent that neither would fit the role as they were both licensed at the system level plus HA4i was more than they needed because it had all bells and whistles associated with a High Availability product while DR4i just didn’t have the object capabilities required. So we had to look at what we could do to build something that sits in the middle and license it in such a manner that would allow the price to be fair for all parties.

Originally the product was going to be used in a LPAR to LPAR scenario because the plan was to use the HA4i product with some removed functionality, however one of the MSP’s decided that managing lots of LPAR’s even if they are hosted as VM’s under an IBM i host would entail too much management and effort. The RTO was not going to be the main driver here only the RPO, so keeping the overhead of managing the solution would be a deciding factor. We looked at how to implement the existing redirection process used for mapping libraries that HA4i and DR4i use, it soon became very apparent to us that this would not be ideal as each transaction being processed would require a lot of effort to set the target object. So we decided to look at how we could take the iASP technology we had built many years ago for our RAP product and structure it in such a manner which would meet all of the requirements.

After some discussion and trials we eventually had a working solution that would deliver an effective iASP based replication process. Next we needed to set the licensing to allow flexibility in how it could be deployed. The original concept would be to set the licensing at the library level as most clients would be basing their recovery on a number of libraries so adding the ability to manage the number of licenses against the number of libraries was started. What at first seemed to be a simple task soon threw up more questions than answers! The number of libraries even with a range was not going to be a fair practice for setting our price, some libraries would be larger than others and have more activity which would generate more activity for the replication process. Also the IFS would be totally outside of the licensing as it has no correlation with a library based object (nesting of directories) so it would need to be managed separately. We also recognized that the Data Apply was based solely on the Journal so library based licensing would not work for it either.

The key to getting this to work would be flexibility, we needed to understand this from the MSP’s position, the effort required to manage the set up and licensing had to be simple enough for the sales person to be able to go in and know what price he should set. So we eventually came back to the IBM tier based pricing, even though we have the ability to license all the way back to the object, CPU, LPAR, Journal etc. We needed to give the MSP flexibility to sell the solution at an affordable price without complex license charts. We also understand that a MSP would grow the business and probably have additional resources available for new clients in advance, so we decided that the price had to be based on the clients system and not on the pair of systems being used.

LVLT4i is just getting started, its future will be defined by the MSP community who use it because they will drive the development of new features. We have always felt that Availability is best handled by professionals because Availability is not a one off project, it has to evolve as the clients requirements evolve and develop. Our products hopefully give clients the ability to move through a natural progression from DR to HA. Just because you don’t need High Availability today doesn’t mean you wont later, we have yet to find anyone who doesn’t need to protect their data. Having that data protected to the nearest transaction at an affordable cost is something we want to provide.

If you feel LVLT4i is right for you let us know, we will be happy to put you in touch with one of the partners we are working with to discuss your needs. If you would like to discuss other opportunities for the product such as data aggregation or centralized storage let us know, we are always happy to see if the technology we have, fits other interests.


Jun 05

What does V8R0 of HA4i look like?

While we wait for IBM to get back to us about our PowerVM activations (3 days and counting, I often wonder does IBM want to service clients?) I thought I would start to show some of the changes we have made in the next release of HA4i. The announcement date for the next release is a little way off as we still have to get the manual and new PHP interfaces finished, but we all feel excited about some of the new capabilities so we thought we would start to share.

As the PHP interface is not completed and we have found the IBM Access for Web product is performing very well, we thought it would be an ideal opportunity to show it off at the same time we display some of our new features. So far the displays have been pretty pleasing with no problems in showing the content effectively. Again we will point out the fact that the web interface is being run on one system (shield7) and the system running HA4i is another (shield8), the ability to launch a 5250 session from the web interface to another system without the web software running on that system is pretty neat in our view.

The first screen we will share is the main monitoring screen, this is a screen shot of the 5250 green screen output using the standard Client Access emulator.

5250 Roleswap Status Green screen

5250 Roleswap Status Green screen

Here is the IBM Access for Web output of the same screen, we have placed arrows and markers to show some of the features which we will describe below.

Roleswap Status Access for Web

Roleswap Status Access for Web

Arrow 1.
A)These are the options that are available against each of the environment definitions, these can be used to drill down into more specific data about each of the processes involved in the replication of the objects and data.

B)You will notice that we can end and start each environment separately, there is also an option on the operations menu which will start and stop every environment at once.

C) You can Roleswap each individual environment, the previous version only allowed a total system Roleswap.

Arrow 2.
A) Some environments should not allow Roleswaps to be carried out, we have defined 2 such environments to replicate the JQG4i data. Because the data is only ever updated on the generating system and each system has its own data sets you would never want to switch the direction of replication. The Y/N flags show that the BATCHTST environment can be switched while the JQG4i environments cannot.

Arrow 3.
A) These are the environment names, each environment runs its own configurations and processes.

Arrow 4.
A) This is the mode of the environment on this system *PROD states that this is a source system where the object changes are captured while the *BACKUP is where the changes will be applied. when viewing the remote system these roles will be reversed.

Arrow 5.
A) If there are any errors or problems found within any of the replication processes you should not carry out a roleswap, HA4i retrieves the status from both the local and remote system to determine if an environment is capable of being roleswapped based on the state of the replication processes. As you can see if an environment should not be roleswapped the entry is marked as *NA.

Arrow 6/7/8.
A) This is the state of the various replication processes, *GOOD states that there are no errors and everything that should be running is. *NOCFG states that no configurations exist that require the replication process to be running. Data status is the journal apply process and which could encompass more than one apply process if there is more than one journal configured to the environment.

Arrow 9.
A) You can view the configs from any system but changes to the configs can only be carried out on the *BACKUP system. the configuration pages can be accessed using this button (F17 on the 5250 Green screen).
B) The Remote Sys button (F11 on the 5250 green screen) just displays the remote system information.

There are a lot more new features in the next release which will make HA4i more competitive in complex environments, over the next few weeks/months we will show you what they are and why they are important. The big take away from above is the ability to define a much more granular approach to your replication needs. Becuase we can define multiple systems and multiple environments HA4i is going to be a lot more useful when you need to migrate to new hardware and expand data replication beyond 2 systems.

We hope that you like the features and if you are looking at implementing a new HA solution or looking to replace an existing one that you consider HA4i.


Feb 12

Adding a Bar Graph for CPU Utilization to HA4i and DR4i

As part of the ongoing improvements to the PHP interfaces we have developed for HA4i and DR4i we decided to add a little extra to the dashboard display. The dashboard display is a quick view of the status for the replication processes, we used traffic lights as indicators to determine if the processes are running OK. Another post recently discussed using a gauge to display the overall CPU utilization for the system but we wanted to take it one step further, we wanted to be able to show just the CPU utilization for the HA4i/DR4i jobs.

We thought about how the data should be displayed and settled on a bar graph, the bars of the graph would represent the CPU utilization as a percentage of the available CPU and would be created for each job that was running in the HA4i/DR4i subsystem. This gave us a couple of challenges because we needed to determine just how many jobs should be running and then allow us to build a table which would be used to display the data. There are plenty of bar graph examples out there which show how to use CSS and HTML to display data, our only difference is that we would need to extract the data from the system and then build the bar graph based on what we were given.

The first program we needed to create was one which would retrieve the information about the jobs that are running that could be called from the Easycom program interface. We have already published a number of tests around this technology so we will just show you the code we added to allow the data to be extracted. To that end we extended the PHPTSTSRV service program with the following function.

typedef _Packed struct job_sts_info_x {
char Job_Name[10];
char Job_User[10];
char Job_Number[6];
int CPU_Util_Percent;
} job_sts_info_t;

int get_job_sts(int *num_jobs, job_sts_info_t dets[]) {
int i,rc = 0,j = 0; /* various ints */
int dta_offset = 0;
char msg_dta[255]; /* message data */
char Spc_Name[20] = "QUSLJOB QTEMP "; /* space name */
char Format_Name[8] = "JOBL0100"; /* Job Format */
char Q_Job_Name[26] = "*ALL HA4IUSER *ALL "; /* Job Name */
char Job_Type = '*'; /* Job Info type */
char *tmp;
char *List_Entry;
char *key_dta;
Qus_Generic_Header_0100_t *space; /* User Space Hdr Ptr */
Qus_JOBL0100_t *Hdr;
Qwc_JOBI1000_t JobDets;
EC_t Error_Code = {0}; /* Error Code struct */

Error_Code.EC.Bytes_Provided = _ERR_REC;
/* get usrspc pointers */
/* memcpy(Q_Job_Name,argv[1],26); */
if(Error_Code.EC.Bytes_Available > 0) {
if(memcmp(Error_Code.EC.Exception_Id,"CPF9801",7) == 0) {
/* create the user space */
if(Crt_Usr_Spc(Spc_Name,_1MB) != 1) {
printf(" Create error %.7s\n",Error_Code.EC.Exception_Id);
if(Error_Code.EC.Bytes_Available > 0) {
printf("Pointer error %.7s\n",Error_Code.EC.Exception_Id);
else {
printf("Some error %.7s\n",Error_Code.EC.Exception_Id);
if(Error_Code.EC.Bytes_Available > 0) {
printf("QUSLJOB error %.7s\n",Error_Code.EC.Exception_Id);
List_Entry = (char *)space;
List_Entry += space->Offset_List_Data;
*num_jobs = space->Number_List_Entries;
for(i = 0; i < space->Number_List_Entries; i++) {
Hdr = (Qus_JOBL0100_t *)List_Entry;
"*INT ",
if(Error_Code.EC.Bytes_Available > 0) {
printf("QUSRJOBI error %.7s\n",Error_Code.EC.Exception_Id);
dets[i].CPU_Util_Percent = JobDets.CPU_Used_Percent;
List_Entry += space->Size_Each_Entry;
return 1;

The program calls the QUSLJOB API to create a list of the jobs which are being run with a User profile of HA4IUSER (we would change the code to DR4IUSER for the DR4I product) and then use the QUSRJOBI API to get the CPU utilization for each of the jobs. We did consider using just the QUSLJOB API with keys to extract the CPU usage but the above program does everything we need just as effectively. As each job is found we are writing the relevant information to the structure which was passed in by the PHP program call.

The PHP side of things requires the i5_toolkit to call the program but you could just as easily (well maybe not as easily :-)) use the XMLSERVICE to carry out the data extraction. We first created the page which would be used to display the bar chart, this in turn calls the functions required to connect to the IBMi and build the table to display the chart. Again we are only showing the code which is additional to the code we have already provided in past examples. First this is the page which will be requested to display the chart.

Copyright © 2010, Shield Advanced Solutions Ltd
All rights reserved.


Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
- Neither the name of the Shield Advanced Solutions, nor the names of its
contributors may be used to endorse or promote products
derived from this software without specific prior written

// start the session to allow session variables to be stored and addressed
// load up the config data
if(!isset($_SESSION['server'])) {
$conn = 0;
$_SESSION['conn_type'] = 'non_encrypted';
if(!connect($conn)) {
if(isset($_SESSION['Err_Msg'])) {
$_SESSION['Err_Msg'] = "";
echo("Failed to connect");
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
td.value {
background-image: url(img/gl.gif);
background-repeat: repeat-x;
background-position: left top;
border-left: 1px solid #e5e5e5;
border-right: 1px solid #e5e5e5;
border-bottom: none;

td {
padding: 4px 6px;
border-bottom:1px solid #e5e5e5;
border-left:1px solid #e5e5e5;

body {
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size: 80%;

td.value img {
vertical-align: middle;
margin: 5px 5px 5px 0;

th {
text-align: left;

td.last {
border-bottom:1px solid #e5e5e5;

td.first {
border-top:1px solid #e5e5e5;

table {
background-position:left top;
width: 33em;

caption {

<?php get_job_sts($conn,"*NET"); ?>

The above code shows the STYLE element we used to form the bar chart, normally we would encompass this within a CSS file and include that file, but in this case as it is just for demonstrating the technology we decided to leave it in the page header. the initial code of the page starts up the session, includes the functions code, loads the config data which is used to make the connection to the IBMi and then connects to the IBMi. Once that is done the function which is contained in the functions.php called get_job_sts is called. Here is the code for that function.

* function to display bar chart for active jobs and CPU Usage
* @parms
* the connection to use

function get_job_sts(&$conn,$systyp) {
// get the number of jobs and the data to build the bars for

$desc = array(
array("Name" => 'NumEnt', "io" => I5_INOUT, "type" => I5_TYPE_INT),
array("DSName" =>"jobdet", "count" => 30, "DSParm" => array(
array("Name" => "jobname", "io" => I5_OUT, "type" => I5_TYPE_CHAR, "length" => "10"),
array("Name" => "jobuser", "io" => I5_OUT, "type" => I5_TYPE_CHAR, "length" => "10"),
array("Name" => "jobnumber", "io" => I5_OUT, "type" => I5_TYPE_CHAR, "length" => "6"),
array("Name" => "cpu", "io" => I5_OUT, "type" => I5_TYPE_INT))));
// prepare for the program call
$prog = i5_program_prepare("PHPTSTSRV(get_job_sts)", $desc, $conn);
if ($prog == FALSE) {
$errorTab = i5_error ();
echo "Program prepare failed <br>\n";
var_dump ( $errorTab );
die ();
// set up the input output parameters
$parameter = array("NumEnt" => 0);
$parmOut = array("NumEnt" => "nbr", "jobdet" => "jobdets");
$ret = i5_program_call($prog, $parameter, $parmOut);
if (!$ret) {
echo("<table cellspacing='0' cellpadding='0' summary='CPU Utilization for HA4i Jobs'>");
echo("<caption align=top>The current CPU Utilization for each HA4i Job on the " .$systyp ." System</caption>");
echo("<tr><th scope='col'>Job Name</th><th scope='col'>% CPU Unitlization</th></tr>");
for($i = 0; $i < $nbr; $i++) {
$cpu = $jobdets[$i]['cpu']/10;
if($i == 0) {
echo("<tr><td class='first' width='20px'>" .$jobdets[$i]['jobname'] ."</td><td class='value first'><img src='img/util.png' alt='' width='" .$cpu/2 ."%' height='16' />" .$cpu ."%</td></tr>");
elseif($i == ($nbr -1)) {
echo("<tr><td class='last' width='20px'>" .$jobdets[$i]['jobname'] ."</td><td class='value last'><img src='img/util.png' alt='' width='" .$cpu/2 ."%' height='16' />" .$cpu ."%</td></tr>");
else {
echo("<tr><td width='20px'>" .$jobdets[$i]['jobname'] ."</td><td class='value'><img src='img/util.png' alt='' width='" .$cpu/2 ."%' height='16' />" .$cpu ."%</td></tr>");
return 1;

The program call is prepared with a maximum of 30 job info structures, we would normally look to define this before the call and set the actual number of jobs to extract but for this instance we simply decided that 30 structures would be more than enough. After the program is called and the data returned we then build the table structure that will be used to display the data. We originally allowed the bar to take up all of the table width but after testing on our system which has uncapped CPU found that we would sometimes get over 100% CPU utilization. We still show the actual utilization but decided to halve the bar width which gave us a better display.

HA4i is running on our system in test so the CPU utilization is pretty infrequent even when we run a saturation test, but the image capture below will give you an idea of what the above code produces in our test environment.


CPU Ultization Bar Chart HA4i

Now we just need to include the relevant code into the HA4i/DR4i PHP interfaces and we will be able to provide more data via the dashboard which should help with managing the replication environment. You can see the original bar chart on which this example was produced here

Happy PHP’ing.


Dec 18

New features added to HA4i

A couple of new features have been added to the HA4i product as a result of customer requests. Auditing is one area where HA4i has always been well supported but as customers get used to the product they find areas they would like to have some adjustments. The object auditing process was one such area, the client was happy that the results of the audits were correct but asked if we could selectively determine which attributes of an object are to be audited as they have some results which while they are correct are not important to them.

The existing process was a good place to start so we decided to use this as the base but while were making changes improve the audit to bring in more attributes to be checked. We determined a totally new set of programs would be required which would include new commands and interfaces, this would allow the existing audit process to remain intact where clients have already programmed them into their schedulers and programs. The new audits would run by retrieving the list of parameters to be checked from a control file and only compare configured parameters. The results have been tested by the client and he has given us the nod to say this meets with his approval. We also added new recovery features which allow out of sync objects to be fully repaired more effectively.

Another client approached us with a totally different problem, they were having problems with errors being logged from the journal apply process due to developers saving and restoring journaled objects from the production environment into test libraries on the production system. This caused a problem because the objects are automatically journaled to the production journal when they are restored, so when the apply process finds the entry in the remote journal it tries to create the object on the target system and fails because the library does not exist. To overcome this we amended the code which supports the re-direction technology for the remote apply process (It allows journal entries for objects in one library to be applied to objects in another library) to support a new keyword *IGNORE. When the apply process finds these definitions it will automatically ignore any requests for objects in the defined library. NOTE:- The best solution would have been to move the developers off the production systems and develop more HA friendly approaches to making production data available, but in this case that was not an option.

We are always learning and adding new features into HA4i, many of them from customer requirements or suggestions. Being a small organization allows us to react very quickly to these requirements and provide our clients with a High Availability Solution that meets their needs. If you are looking for an Affordable High Availability or Disaster Recovery Solution or would like to ask about replacing an existing solution give us a call. We are always happy to look at your needs and see if HA4i will fit your solution requirements and budget.


Dec 07

Adding configuration Capabilities to the HA4i PHP Interfaces

We have been developing the management interface for HA4i our High Availability product in PHP for some time, but we had not got round to looking at how we could extend that interface to allow us configure the various elements of HA4i. While the existing 5250 (Green Screen) configuration panels are very effective in what they do but we wanted bring that capability into the PHP interface.

Until now, to view or update the existing configurations you needed to sign onto each system and go through each individual panel group to update the various elements that configure HA4i. We wanted to pull all of that information into a single screen where you could view the existing configuration and select a particular element to be updated.

The first panel displays the existing configuration with links (buttons) to allow you to update the particular configuration.

Here is a sample of the initial page.

New Configuration Screen

New Configuration Screen

The above screen allows each of the elements which can be updated, if a change occurs which requires the configuration to be replicated between the systems it is automatically handled in the same manner it was with the 5250 screens. We like the fact that we can now update any configuration and restart the processes all from one interface. Selecting the option to update the remote journal configuration will display a list of all available remote journals as can be seen in the sample display below.

Remote Journals available for configuration

Remote Journals available for configuration

As you can see from the display, if the journal is already configured it will be identified and a remove button provided, if it is not already configured a button allows it to be added. Because the remove button simply removes the configuration data it does not need any additional panels, but to Configure requires some of the parameters to be presented so they can be changed if required as can be seen in the sample display below.

Configure a new Remote Journal

Configure a new remote journal

Once submit is pressed on this page the remote journal is added to the configuration and the relevant objects created to allow processing by HA4i. Once this completes the list of configured remote journals is displayed again with the new journal correctly identified.

HA4i Object replication is simply a list of libraries that are to be monitored for changes, we decided to use a selection list to allow the required libraries to be configured and a list of existing configurations. You can select as many libraries as you wish in a single request which are automatically added to the configured list and all objects in the requested libraries marked for auditing so that any changes to the objects are captured and replicated. The display below shows the currently configured library plus a scrollable selection list of those libraries which are not.

Configure the libraries Object Replication

Configure the libraries for Object Replication

Output Queues have a similar interface which lists all available out queues for configuration in the same manner as the list of libraries. The following is a sample display from our test system.

Configure Outq's

Configure Outq'

The default configuration is unique to each system so there are two buttons one for each system to allow the configuration to be updated, we provided drop down options for some of the parameters to ensure the data entered is correct plus any parameters which are restricted are set to be read only. This is what our test configuration looks like.

Configure default settings

Configure default settings

That is all you need to configure HA4i, we do have a couple of filter options and IFS replication at the object level which need some attention but in the main this new interface allows you to configure, control and monitor HA4i from a single interface. The biggest gain for us was the speed at which we could implement changes using PHP and Easycom, when we developed the UIM based interfaces it would take us days just to create a single configuration interface. With Easycom and PHP we managed to build the configuration interface in just over a day.

HA4i is a premier High Availability Solution, we are constantly improving the product and interfaces making it simpler to manage and providing many new features. If you are looking at a new High Availability implementation or would like to discuss replacing an existing solution let us know, you may be surprised at just how easy and affordable our High Availability Solution can be.


Dec 05

New and improved RTVDIRSZ utility

We were recently working with a partner who needed to asses the size of the IFS directories in preparation for replication with HA4i. Before he could start to plan he needed to understand just how large the IFS objects would be and how many objects would need to be journaled. One of the problems he faced was the save of the IFS had been removed from the normal save because it was so large and took too long to carry out.

We had provided the RTVDIRSZ utility sometime ago which would walk through the IFS from a given path and report back to the screen the number of objects found and the total size of those objects. Running the original RTVDIRSZ request took a number of hours to complete and while it gave him the total numbers he would have liked to see a bit more detail in how the directories were constructed.
So we decided to change the programs a little bit and instead or writing the data back out to the screen we would write it to an IFS directory file which could be viewed at leisure and analyzed further should it be required. As part of the update we also changed the information which would be stored in the file, we added a process to show the directory being processed and what size the directory was as well as the number of objects in that directory. Once all of the information had been collected we wrote out the total data just as we had previously.

Here is a sample of the output generated from our test system.

Browse : /home/rtvdirsz/log/dir.dta
Record : 1 of 432 by 18 Column : 1 144 by 131
Control :

************Beginning of data**************
Directory Entered = /home
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/.manager objects = 4 size = 178.0B
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/manifests objects = 83 size = 57.8kB
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/33/1/.cp/nl/es objects = 5 si
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/33/1/.cp/nl objects = 0 size
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/33/1/.cp objects = 0 size = 0
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/33/1 objects = 0 size = 0.0B
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/33 objects = 0 size = 0.0B
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/36/1/.cp/nl/hr objects = 2 si
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/36/1/.cp/nl objects = 0 size
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/36/1/.cp objects = 0 size = 0
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/36/1 objects = 0 size = 0.0B
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/36 objects = 0 size = 0.0B
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/37/1/.cp/nl/hu objects = 2 si
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/37/1/.cp/nl objects = 0 size
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/37/1/.cp objects = 0 size = 0
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/37/1 objects = 0 size = 0.0B
Directory = /home/QIBMHELP/.eclipse/org.eclipse.platform_3.2.2/configuration/org.eclipse.osgi/bundles/37 objects = 0 size = 0.0B
Directory = /home/ha4itst/exclude/dir1 objects = 3 size = 39.0B
Directory = /home/ha4itst/exclude objects = 1 size = 29.0B
Directory = /home/ha4itst/newdir1/newdir2 objects = 2 size = 1.9kB
Directory = /home/ha4itst/newdir1 objects = 0 size = 0.0B
Directory = /home/ha4itst objects = 1 size = 16.5kB
Directory = /home/QWEBQRYADM objects = 1 size = 18.0B
Directory = /home/ftptest/NEWDIR/test1 objects = 0 size = 0.0B
Directory = /home/ftptest/NEWDIR objects = 0 size = 0.0B
Directory = /home/ftptest objects = 0 size = 0.0B
Directory = /home/jsdecpy/log objects = 1 size = 237.0kB
Directory = /home/jsdecpy objects = 0 size = 0.0B
Directory = /home/rtvdirsz/log objects = 1 size = 49.9kB
Directory = /home/rtvdirsz objects = 0 size = 0.0B
Directory = /home objects = 0 size = 0.0B
Successfully collected data
Size = 442.3MB Objects = 1541 Directories = 427
Took 0 seconds to run

************End of Data********************

Unfortunately the screen output cannot contain all of the data but you get the idea.. Now you can export that data to a CSV file or something and do some analysis on the results found (finding the directory with the most objects or the biggest size etc.)

The utility is up on our remote site at the moment, if I get chance I will move it to the downloads site.
If you are looking at HA and would like to use the utility to understand your IFS better let me know. we can arrange for copies to be emailed to you.


Oct 19

Playing around with LOB objects

As part of the new features we are adding to the HA4i product we needed to build a test bed to make sure the LOB processing we had developed would actually work. I have to admit I was totally in the dark when it comes to LOB fields in a database! So we had a lot of reading and learning to do before we could successfully test the replication process.

The first challenge was using SQL, we have used SQL in PHP for a number of years but to be honest the complexity we got into was very minimal. For this test we needed to be able to build SQL tables and then add a number of features which would allow us to test the reproduction of the changes on one system to the other. Even now I think we have only scratched the surface of what SQL can do for you as opposed to the standard DDS files we have been creating for years!

To start off with we spent a fair amount of time trawling through the IBM manuals and redbooks looking for information on how we needed to process LOB’s. The manuals were probably the best source of information but the redbooks did give a couple of examples which we took advantage of. The next thing we needed was a sample database to work with (if we swing between catalogues, libraries, tables, files too often we are sorry!) which would give us a base to start from. Luckily IBM has a nice database they ship with the OS that we use could for this very purpose, it had most of the features we wanted to test plus a lot more we did not even know about. To build the database IBM provides a stored procedure (CALL QSYS.CREATE_SQL_SAMPLE (‘SAMPLE’)), we ran the request in Navigator for i (not sure what they call it now) using the SQL Scripts capabilities and changed the parameter to ‘CORPDATA’. This created a very nice sample database for us to play with.

We removed the QSQJRN set up as we do not like data objects to be in the same library as the journal and then created a new journal environment. We started journaling of all the files to the new journal and added a remote journal. One feature we take advantage of is the ability to start journaling against a library which ensure any new files created in the library are picked up and replicated to the target. The whole setup was then replicated on the target system and configured into HA4i.

As we were particularly interested in LOBs and did not want to make too many changes to the sample database we decided to create our own tables in the same library. The new files we created used the following SQL statements.

CREATE TABLE corpdata/testdta
(First_Col varchar(10240),
Text_Obj CLOB(10K),
Bin_Obj BLOB(20M),
Forth_Col varchar(1024),
Fifth_Col varchar(1024),
CREATE TABLE corpdata/manuals
(Description varchar(10240),
Text_Obj CLOB(10K),
Bin_Obj BLOB(1M),

We will discuss the tstamp_column fields later as these are important to understand from a replication perspective. We checked the target and HA4i had successfully created the new objects for us so we could now move onto adding some data into the files.

Because we have LOB fields we cannot use the UPDDTA option we have become so fond of, so we needed to create a program that would add the required data into the file. After some digging around we found that C can be used for this purpose (luckily as we are C programmers) and set about developing a simple program (yes it is very simple) to add the data to the file. Here is the SIMPLE program we came up with which is based on the samples supplied by IBM in the manuals.



int main(int argc, char **argv) {
FILE *qprint;



/* set up the link */
/* length of the file names */
txt_file.name_length = strlen(txt_file.name);
bin_file.name_length = strlen(bin_file.name);
/* SQL Option */
txt_file.file_options = SQL_FILE_READ;
bin_file.file_options = SQL_FILE_READ;


VALUES ('Another test of the insert routine into CLOB-BLOB Columns',
'Text in the next column',
'This is the text in the last column of the table....',

goto finished;


fprintf(qprint,"There seems to have been an error in the SQL?\n"



The program takes 2 strings which are the paths to the CLOB and BLOB objects we want installed into the table. This program is for updating the TESTDTA table, but is only slightly different to the program required to add records to the MANUALS table. As I said it is very simple, but for our test purposes it does the job..

Once we had compiled the programs we then called the program to add the data, it doesn’t matter how many times we called it with the same data so a simple CL script in a loop allowed us to generate a number of entries at a time. The :txt_file and :bin file are references to the objects we would be writing to the tables, the manuals have a very good explanation on what these are and why they are useful.

Once we had run the program a few times we found the data had been successfully added to the file. The LOB data however, does not show up in a DSPPFM but is instead represented by *POINTER in the output as can be seen below.

Here is the DSPPFM output which relates to the LOB/CLOB Fields.


The same thing goes for the Journal entry.

Column *…+….1….+….2….+….3….+….4….+….5
10201 ‘ ‘

We have an audit program which we ran against the table on each system to confirm the record content is the same, this came back positive so it looks like the add function works as designed!

The next requirement was to be able to update the file, this can be accomplished with SQL from the interactive SQL screens which is how we ecided to make the updates. Here is a sample of the updates used against one of the files which updates the record found at rrn 3.

'This updates the character field in the file after reusedlt changed to *no in file open2'
WHERE RRN(manuals) = 3

Again we audited the data on each system and confirmed that the updates had been successfully replicated to the target system.

That was it, the basic tests we ran confirmed we could replicate the creation and update of the SQL tables which had LOB content. We also built a number of other tests checked that the ALTER table and add of new views etc would work but for the LOB testing this showed us that the replication tool HA4i could manage the add, update and delete of records which contained LOB data.

I have to say we had a lot of hair pulling and head scratching when it came to the actual replication process programming, especially with the limited information IBM provides. But we prevailed and the replication appears to be working just fine.

This is where I point out one company who is hoping to make everyone sit up and listen even though it is nothing to do with High Availability Solutions. Tembo Technologies of South Africa has a product which we were looking at initially to help companies modernize their databases, moving from the old DDS based file system to a new DDL based file system. Now that I have been playing with the LOB support and seen some of the other VERY neat features SQL offers above and beyond the old DDS technology I am convinced they have something everyone should be considering. Even if you just make the initial change and convert your existing DDS based files into DDL the benefits will be enormous once you start to move to the next stage of application modernization. Unless you modernize your database the application you have today will be constrained by the DDS technology. SQL programming is definitely something we will be learning more about in the future.

As always, we continue to develop new features and functionality for HA4i and its sister product JGQ4i. We hope you find the information we provide useful and take the opportunity to look at our products for your High Availability needs.


Oct 12

HA4i and IFS Journal entry replay

One of the features we have been working on recently is the ability to replay journal entries generated by IFS activity. The HA4i product does support the replay of IFS journal entries but only via the *IBM (APYJRNCHG) apply process. Having seen the improvements we had gained by implementing our own apply process for DB journal entries we decided that we needed to offer the same capabilities with the IFS journal entries.

The technology for applying updates to IFS objects using the journal entries had been partially developed for sometime, however development stopped when we found that the JID and Object ID could not be maintained between systems using IBM API’s. You might ask why? Well because some of the journal entries deposited into the journal do not have the path to the object and only the Object ID we needed some method to extract the true path to the object from the content of the journal entry. As the JID and Object ID are different we could not use the API’s that are available to convert those ID’s into the path. We did ask IBM if they would provide a solution in much the same manner as they do for Database file (QDBRPLAY) and Data Area – Data Queue (QjoReplayJournalEntry) which protect the JID of the created object, this in turn allows us to use the API’s to extract the actual Path of the object using the JID contained in the journal entry. But they said it could not be done (they already have to do it for the APYJRNCHG but would not expose it to others) and suggested we came up with a table or other technology which would allow us to track each and every IFS object, we thought that would be a nightmare to handle especially as one of our clients had to split his IFS over 3 journals just because he hit the maximum number of objects which can be journaled to a single journal! Still, when push came to shove we bit the bullet and built a technology to track the IFS objects which would then allow us to manipulate the IFS objects using the journal entries.

We faced a number of challenges with the replication technology such as security and CCSID conversion, but eventually we got to the bottom of the pile and the apply of IFS generated updates now works. We are still surprised people use the IFS especially with the abundance of better storage solutions out there, but we can now provide our own apply process for the IFS journal entries. Tracking of the JID and Object ID is now carried out very effectively without the use of a DB table and it is very fast and has a very low CPU impact.

We are not finished yet though, we are now working on implementing support for some of the more obscure DB2 capabilities plus the Journal Minimal Data option with *FLDBDY and *FILE support. We are also experimenting with Identity columns and User Defined Types to name a few. You may not use these capabilities now but having built the tests to allow us to test them within HA4i, I must admit I am going to use them a lot more in the future.

HA4i continues to improve as a solid High Availability solution, having already built a lot of new features in the latest Version(7.1) we now have another set of features ready for release in the next PTF. If you are looking at HA or want to reduce the cost of your current implementation give us a call, we may surprise you with what we can offer. We might be small but that does not stop us from developing first class solutions and at a cost you can afford.