On Mon, 2012-01-02 at 15:47 -0900, Erinn Looney-Triggs wrote: > While digging through and trying to investigate a file system slowdown > that may or may not be IPA related, I noticed an odd thing on my RHEL 5 > and 6 based systems, the lastlog file was bloody huge: > > -rw-r--r-- 1 root root 469419202628 Jan 3 00:20 /var/log/lastlog > > Or for those of us who don't count that high . > > -rw-r--r-- 1 root root 438G Jan 3 00:20 /var/log/lastlog > > Now really it isn't that big: > > erinn@uat ~ $ du -sh /var/log/lastlog > 64K /var/log/lastlog > > However, and I am no expert here, some backup programs will choke hard > on this file, because it appears all that empty space will actually get > nulled out, or at least this is happening to me with Bacula 5.0.2 on > RHEL 5. More investigation into this part is necessary though... > > Now at a guess, this is probably related to this blog post: > http://linuxshellaccount.blogspot.com/2007/11/trimming-space-in-var-problem-with.html > > That article was written for Solaris but it sure seems to be applicable > to Linux as well. Though the multiples aren't the same. > > Frustratingly, this does not seem to be the case with all of my systems, > only some of them. I have multiple RHEL 5 and 6 instances exhibiting > this issue, and one RHEL 5 system that is not. > > This is probably a result of IPA choosing ludicrously high UIDs to avoid > collisions (which is fine, no bashing here). > > Can anyone else confirm? Lend more insight?
I can confirm. apparently lastlog programmers decided that using sparse files to implement a hash table where the key is the uid number was a good idea ... Can you please file a bug against RHEL and CC me ? I am not sure what we do for RHEL5/RHEL6 as I don't know if the lastlof file format changes is considered an aBI change but we can certainly prevent this from happening in Fedora and RHEL7. I think, meanwhile you may want to exclude lastlog from backups or bzip2 it before backing it up. Thanks for reporting this. Simo. -- Simo Sorce * Red Hat, Inc * New York _______________________________________________ Freeipa-users mailing list [email protected] https://www.redhat.com/mailman/listinfo/freeipa-users
