On 01/22/2015 09:00 AM, Lukas Slebodnik wrote:
On (21/01/15 11:22), Orion Poplawski wrote:
> On 01/06/2015 05:06 PM, Orion Poplawski wrote:
>> We're having some trouble with sssd on centos 7 under load on a VPS. 389ds
>> ldap server for id/auth. Part may be an issue with the VPS, but I'm trying
to
>> track down all possible issues.
>>
>> Also, we realized that we were running in a bit of a bad state - the primary
>> ldap server was not available, but the backup was.
>
>> Trouble:
>> (Tue Jan 6 22:30:31 2015) [sssd[be[default]]]
>> [sss_ldap_init_sys_connect_done] (0x0020): sdap_async_sys_connect request
failed.
>> (Tue Jan 6 22:30:31 2015) [sssd[be[default]]] [sdap_sys_connect_done]
>> (0x0020): sdap_async_connect_call request failed.
>
> I ended up filing
https://fedorahosted.org/sssd/ticket/2562 as it seems like
> sssd's handling of the ldap connection is not ideal.
>
I checked strace log file and I can confirm you are right.
But I have no idea how to reproduce or fix it.
Output from strace is not sufficient.
We would need to see sssd log files with high debug_level.
You mentined the most problematic part of VPS is I/0.
So increasing debug_level can just complicate situation.
I'll see what I can do.
I can just give you an advice about *sync calls you mentioned in
ticket.
It is not visible in strace log but fdatasync() and msync() are used on file
descriptor of sssd cache (/var/lib/sss/db/cache_*.ldb. They are used in ldb/tdb
for transactions.
If you do not need offline authentication you can mount tmpfs to directory
/var/lib/sss/db/.
tmpfs /var/lib/sss/db/ tmpfs
size=300M,mode=0700,noauto,rootcontext=system_u:object_r:sssd_var_lib_t:s0 0 0
That is a good idea, thanks. Offline auth should work though unless the
machine got rebooted, correct?
--
Orion Poplawski
Technical Manager 303-415-9701 x222
NWRA, Boulder/CoRA Office FAX: 303-415-9702
3380 Mitchell Lane orion(a)nwra.com
Boulder, CO 80301
http://www.nwra.com