On 5 Feb 2010, at 14:23, Rainer Toebbicke wrote: > aklog -setpag does not work as expected under Openafs 1.4.11, under RHEL 5.
Basically, we've not supported changing the PAG of your parent on Linux for a while now. There's no easy way of fiddling with the group membership of the parent process without breaking loads of locking assumptions, or using things that we aren't allowed to have access to. Hence the warning in the manpage. That said, we haven't consciously set out to break it either, so if this is something that works in 1.4.x, but not in 1.4.11, and is unrelated to a kernel version change, I'd be interested to hear more about it. In 1.4.x, PAG membership is still determined by a processes group list (in 1.5.x, we use the keyring as the only source of PAG information) - so the existence or not of a keyring shouldn't be a problem. However, it does occur to me that we are now using keyrings for PAG garbage collection - as walking the process table ceased being an option. It's possible that what's happening is that we are, through some fluke, succeeding in changing the parent's group ID. However, we can't (on kernels of RHEL5 vintage) set the keyring of the parent safely. So only the child has a keyring containing that PAG. When the child dies, the keyring's reference count hits 0, and so it is garbage collected. This triggers garbage collection of the associated tokens, and so the parent loses out. I can't think of any easy way to solve this, though, beyond reiterating "-setpag isn't supported on Linux". Ideas are welcome. Cheers, Simon. _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
