Red Hat Bugzilla – Bug 147611
autofs queries for all entries in even large automountmaps.
Last modified: 2007-11-30 17:06:54 EST
Description of problem:
Our ldap servers are being overwhelmed by queries from the Linux
automounter (nearly all RH of some version from 7.2 to Enterprize 3.0)
for all entries in certain maps. Our auto.home is the main problem -
it has over 3000 entries and these are all getting served up every
second or so with the result that the LDAP servers are experiencing
extremely high load and slow response.
Now I'm unable to distinguish for certain if the requests come every
time somone logs in, in which case this would be a bug whereby the
wrong query is being generated. (IE, the automounter should ask for
just the one entry with filter of "(&(objectclass=nisObject)
(cn=<USER>))" rather than just "(&(objectclass=nisObject))" as it
appears in our access logs. The frequency of the requests along with
the & in the existing queries makes me suspect this is the case.
If on the other hand these queries are generated at the timeout
interval and the automount is reloading the map, then I would say
that if "nobrowse" is set, the automounter should not try to get all
the map information but should just query for entries 'on demand'
(ie, query for a specific entry when that directory is accessed. I
realize there are client-side performance advantages to getting the
whole map and maintaining a hash table, but if there is not someway
to tell the automounter not to load the entire map, then it will
never scale to an enterprise level.
Version-Release number of selected component (if applicable):
(don't know about other versions.)
Steps to Reproduce:
1.Just set up the machine as a native LDAP client - it will happen.
As described. LDAP Servers spending all their time shovelling out
Should be query for 1 entry when a given directory is accessed, at
least for 'nobrowse' maps.
Created attachment 110889 [details]
LDAP access log extract showing problem query.
Thanks for the bug report. We'll work to get this into the upcoming update
The code looks to be doing the right thing, so I would need some debug logs from
the automounter to make progress on this.
Unfortunately, AS2.1 is no longer being updated (except for security fixes).
Can you reproduce this problem with RHEL 3 or RHEL 4? They both run the same
version of the automounter, so reproducing on either OS will suffice.
I'ver heard no resonse on this. I'm closing the bug. Please refile against
RHEL 4 if you run into the problem there.