21 June 2007

DPM 1.5.10 -> 1.6.4 upgrade path broken in YAIM

As reported at yesterdays storage meeting, the upgrade path from DPM 1.5.10 to 1.6.4 is broken in YAIM 3.0.1-15. The different versions of DPM require database schema upgrades in order to be able to handle all of the SRM2.2 stuff (space reservation etc). YAIM should contain appropriate scripts to perform these upgrades, but it appears that they appropriate code has been removed, meaning that it is no longer possible to move from schema versions 2.[12].0 in v1.5.10 of DPM to schemas 3.[01].0 in v1.6.4. We stumbled upon this bug when I asked Cambridge to upgrade to the latest DPM in an attempt to resolve the intermittent SAM failures that they were experiencing. A fairly detailed report of what was required to solve the problem can be found in this ticket:

https://gus.fzk.de/pages/ticket_details.php?ticket=23569

It should be noted that for some reason (a bug in a YAIM script?) the Cambridge DPM was missing two tables from the dpm_db database. These were dpm_fs and dpm_getfilereq (I think). This severely hindered the upgrade since we were trying to upgrade the schema, which was successful, but then the DPM wouldn't start. A restore of the database backup, then an upgrade to DPM 1.6.3 then onto DPM (I'm keeping a close eye on the SAM tests...). Sites should be aware that they may need to follow the steps detailed in this link while performing the database upgrade.

https://twiki.cern.ch/twiki/bin/view/LCG/DpmSrmv2Support

After the installation, the srmv2.2 daemon was running and the SRM2.2 information was being published by the BDII. This is all good. If you end up using yaim 3.0.1-16, it should not be necessary to manually install the host certificates for the edguser.

In summary, the 1.5.10 to 1.6.4 upgrade was a lot of work. Thanks to Santanu for giving me access to the machine. This problem raises issues about sites keeping up to date with the latest releases of middleware. Although there were problems with the configuration of 1.6.4, v1.6.3 has been stable in production for a while now. I'm not really sure why some sites hadn't upgraded to that. It would be great if every site could publish the version of the middleware that they are using. In fact, such a feature may be coming very soon. Just watch this space.

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