PXPlus crashing after error 61

Loren Doornek · February 15, 2024, 02:32:50 PM

We have a strange PXPlus crash occurring at one client, using a routine that is used at multiple clients.

The routine gets an error 61 (Authorization failure) when issuing a LOCAL command to localize several variables. At that point, the SETERR branch is taken, and the routine tries to close files. The PXPlus session then crashes when closing one particular file (the same file every time).

I don't really have a clue what would cause an error 61 on a LOCAL command!

- I've removed the LOCAL command that was getting an error. The error then occurs on a different line that is also issuing a LOCAL command, and the session still crashes.
- I've renamed the particular file that is being closed every time the session crashes (thus leaving it in place on the hard drive), then re-created the file. Still crashes.

Before the system crashes, I print the MSG(-1) to a trace file, but it is blank.

We suspect a memory/swap file issue, so I also dump the contents of the Linux "free" command to text file immediately after the error 61. The file shows that there is over 2megs of free memory at that moment, so it wouldn't seem to be an issue with allocating memory for the LOCAL command. I don't know if the swap file is configured correctly, but it does show swap file available but not being used (or only a tiny amount of swap used).

The client is running PXPlus version 12.50 on a Linux server running RedHat 7.9.

Any suggestions on how to resolve this, or other ideas on what to check?

James Zukowski · February 15, 2024, 03:35:32 PM

The only time we run into the Error 61 problem is when the user hasn't set up the WindX authorization properly. Why it's happening on a LOCAL statement or with a particular server file (I presume) is a curiosity indeed.

jasonc · February 15, 2024, 03:36:30 PM

Loren,
If you suspect a problem with memory limits, you also need to consider the limit that an individual session can use.
Check prm('SZ') and prm('IZ').

If prm('IZ') is off, I would turn it on and see if the problem goes away.
If it does, then you can decide if you want to leave it on or if you instead prefer to increase the prm('SZ') to allow each session more memory, but not unlimited.
If it doesn't, back to square one.

Mike King · February 15, 2024, 04:09:26 PM

Loren

You could be facing a OS compatibility issue. There never was a version 12.50 for any version of Redhat 7. The latest Redhat release for version 12.50 was Redhat 6.

You can see all the versions of PxPlus 12.50 at https://home.pvxplus.com/downloads/pxp1250/

If you want to run Redhat 7.9 you likely will need to use a newer PxPlus built for/on that release -- Version 14 PxPlus 2017 -- although even that release would have been made for an earlier version of Redhat 7.

Redhat 7.9 was only released in 2020, PxPlus 12.50 was released in 2015.

Loren Doornek · February 15, 2024, 04:21:59 PM

James, like you, I've only seen an error 61 in relation to Windx installations. This process is running as a cron process on the Linux server, so Windx isn't involved. I suspect the error 61 relates to some permission denied at the OS level.

Jason, thanks for the suggestion on checking the 'IZ'. I did run the process and dump the PRM to a trace file, just to confirm that the 'IZ' parameter is enabled when run as a cron. It is enabled, so the process shouldn't be encountering memory limits.

Loren Doornek · February 15, 2024, 04:28:01 PM

Mike - Thanks for that info. I wasn't aware of these version issues since I don't handle the installs, so I appreciate your detailed explanation!

We did just update them a few minutes ago to the latest 12.5 build, but that didn't help, so we'll try installing v17 and see if that resolves the issue.

Mike King · February 15, 2024, 06:11:49 PM

I think you may have misunderstood my comment.

There has never been a version of release 1250 of PxPlus built on nor tested on Redhat 7. That is not to say version 1250 won't work on that Redhat version, just that there may be compatibility issues.

If you are running Redhat version 7 you should use a version of PxPlus that was compiled on and tested on Redhat 7.

Loren Doornek · February 15, 2024, 06:27:01 PM

Mike - We had already done the 12.5 update before I read your comments about versions, and I mentioned it just to confirm that the 12.5 update didn't resolve the issue. Sorry for the confusion - I should have made that more clear! We understand that 12.5 probably has some issues running on RH7.9, so we're working on updating to 17 now. Not sure if we want to do that just before a long weekend, tho, so we might wait until Tuesday. I'll keep you posted.

Loren Doornek · February 21, 2024, 07:08:30 PM

As a followup, updating the client to PXPlus version 17 resolved the issue - we haven't seen any crashes since the update.

Thanks, Mike, for your detailed explanation of the versions available for the OS release, and thanks to James and Jason for the debugging suggestions!

Mike King · February 21, 2024, 07:48:30 PM

Glad its been resolved.

Over the years I have seen a variety of weird OS compatibility issues so I always suggest you run a version of PxPlus compiled and tested AFTER the release date of any OS. In your case, while v12.50 may have started and appeared to run on Redhat 7, it was compiled and tested on Redhat 6.