Post by ShivaPost by Keith DickThe TMFCOM INFO AUDITDUMP command will show whether TMF is configured to dump audittrail files to tape or not. All you need to learn from it is whether audit trail dumping is enabled or not. If it says that no audittrail dumps are configured, or that audittrail dumps are configured but disabled, then your audittrail files are not being dumped to tape before being purged.
Hmm, it did provide me enough information about the audit dump. And yes, audit dump is enabled. So I'm good to go! :)
Post by Keith DickIf the audittrail files are not dumped to tape, then the information available in the audittrails will go back only as far as the oldest audittrail file that is still online. If the audittrail files are dumped to tape, then a program such as SNOOP or one that uses the TMF audit trail reading library can ask TMF to restore older audittrail files from those tapes when you want to look at information older than what is in the earliest audittrail files that still are online. The tapes are retained at least as far back as the most recent online dump, possibly longer.
I don't know how to find if the files are dumped to tape. I have three files in the audit volume. So I guess that files are produced per day?
If the files are produced once per day, I think it would be a coincidence, unless your site has set up a daily job that runs a TMFCOM NEXT AUDITTRAIL command. The way it normally works is that the TMF configuration defines the maximum size for those individual files in an audittrail, and whenever one of the files becomes full storing the records that describe the changes made to audited files, TMF switches to the next file in the series. If I remember correctly, it actually creates the next file some time in advance of when it needs the file, so switching to it happens essentially instantly.
How quickly an individual file in the audit trail fills up depends on its configured size, the average transaction rate, and the average size of the changes in a transaction. TMF might switch to a new audit trail several times a day, or it might go several days between times it needs to switch to the next file.
If you want to see how many other audittrail files are available on tape (or on a disk backup area, I forgot to mention that audittrail dumps can be sent to another disk), I believe a command like this will do it:
TMFCOM INFO DUMPS, BRIEF, STATUS ASSIGNED, TYPE AUDITDUMP
I have not done much about managing TMF, so I'm not very familiar with the commands. I'm just going by the description in the manual. I believe the output from this command will show in the first column the names of the audittrail files that have accessible backups, and in the third column the dates the dumps were done. You would only need this information to check how far back in time audittrail files are still available. If you make a request for an old audittrail file through the audit trail reading library, TMF will figure out how to retrieve that file and start reading it.
I see Tone also answered with a different command. He probably is more familiar with this aspect of TMF than I am, so his answer might be better.
You do not have to be logged on as a privileged user in order to use this command to see what audittrail files are still known to TMF.
Post by ShivaPost by Keith DickAn OCB is an open control block and DISCOPEN is a name used in Measure commands to configure recording of information about disk file opens. Tone is mentioning that there is an indirect way to learn the userid responsible for a change, even though the userid is not recorded by TMF. Measure is the NonStop tool for collecting data from a running system that lets you analyze the performance of the system, to help you find where bottlenecks are. A "measurement" is happening when you have asked Measure to gather and record various bits of information. Some sites run measurements continuously so that if a slowdown occurs, they will have data to examine to figure out what caused the slowdown. Some sites start measurements only when they recognize that a performance problem is happening.
Hmm, makes sense. I'll check with my admin team if that's enabled! Good one! Let's see if that brings out anything.
And btw, I did study a few pages from Section 5 of TMF programmer's guide. Without any examples it seems a bit hard to grasp at first sight. But as I kept pushing I was able to get some knowledge out of it, and as far as I see I can use TAL, C, COBOL as languages that I can program this from? Occasionally I see TACL, but I'm not sure if that can be coded in TACL?
You cannot use the TMF audit trail reading library from TACL. I would recommend using it from C or TAL, or rather CCOMP or EPTAL -- I believe it cannot be used from non-native code.
Something I think I did not mention before is that a program that uses the TMF audit trail reading library must be licensed and must be run by SUPER.SUPER. That might make it difficult for you to experiment with it. The reason for that restriction is that the audit trail contains the contents of data records from any audited file that has been changed, regardless of the file security settings on those files, so if use of the TMF audit trail reading library were available to any user, that could reveal data that user should not be able to see.
Post by ShivaAnd anyways, do any of you have any such sample programs like what I'm trying to write? It would be a great help if you did and if you are able to share it with me. Because the TMF programmer's guide does not have a single example though it has all the explanation for procedure calls.
It'd give me a good place to start writing my code if I get to see some example. Any language is fine. Thanks for all your help already :)
I will send an example to you via email, since I think it is too large to be reasonable to post here.