[SSSD-users] sssd troubles under load

Jakub Hrozek jhrozek at redhat.com
Thu Jan 8 18:54:40 UTC 2015


On Thu, Jan 08, 2015 at 09:31:16AM -0700, Orion Poplawski wrote:
> On 01/06/2015 11:32 PM, Jakub Hrozek wrote:
> > On Tue, Jan 06, 2015 at 05:06:39PM -0700, 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.
> >>
> >>  Some logs:
> >>
> >> General question, is this bad?:
> >> (Tue Jan  6 23:17:43 2015) [sssd[be[default]]] [sdap_get_users_done]
> >> (0x0040): Failed to retrieve users
> > 
> > This can be caused by many things, we neer more context..in general, the
> > LDAP search has failed and SSSD would fall back to cached entries.
> 
> Okay, appears to be a simple "unknown user" type of response:
> 
> (Thu Jan  8 15:50:47 2015) [sssd[be[default]]] [be_get_account_info] (0x0100):
> Got request for [4097][1][name=contracts-grants]
> (Thu Jan  8 15:50:47 2015) [sssd[be[default]]] [sdap_get_users_done] (0x0040):
> Failed to retrieve users
> 
> contracts-grants is not in LDAP.
> > 
> >>
> >> see that fairly frequently.
> >>
> >> 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.
> >> (Tue Jan  6 22:30:36 2015) [sssd[be[default]]] [resolv_gethostbyname_done]
> >> (0x0040): querying hosts database failed [5]: Input/output error
> >> (Tue Jan  6 22:30:36 2015) [sssd[be[default]]] [fo_resolve_service_done]
> >> (0x0020): Failed to resolve server 'server.com': Timeout while contacting
> >> DNS servers
> >> (Tue Jan  6 22:30:36 2015) [sssd[be[default]]] [be_resolve_server_process]
> >> (0x0080): Couldn't resolve server (server.com), resolver returned (5)
> > 
> > This seems like the core issue, can you resolve server.com from outside
> > SSSD (with dig, maybe) ?
> 
> In general, yes.  But it seems that some kind of load/network issue caused a
> temporary failure.  We've since added entries to /etc/hosts to try to prevent
> this from happening again.
> 
> > 
> >> (Tue Jan  6 22:30:45 2015) [sssd[be[default]]]
> >> [sss_ldap_init_sys_connect_done] (0x0020): sdap_async_sys_connect request
> >> failed.
> >> (Tue Jan  6 22:30:45 2015) [sssd[be[default]]] [sdap_sys_connect_done]
> >> (0x0020): sdap_async_connect_call request failed.
> >> (Tue Jan  6 22:30:45 2015) [sssd[be[default]]] [fo_resolve_service_send]
> >> (0x0020): No available servers for service 'LDAP'
> >> (Tue Jan  6 22:30:45 2015) [sssd[be[default]]] [sdap_id_op_connect_done]
> >> (0x0020): Failed to connect, going offline (5 [Input/output error])
> >> (Tue Jan  6 22:30:45 2015) [sssd[be[default]]] [be_run_offline_cb] (0x0080):
> >> Going offline. Running callbacks.
> > 
> > Here SSSD goes offline and the front end would switch to using the
> > cache.
> 
> 
> >> (Tue Jan  6 22:33:08 2015) [sssd[be[default]]] [get_single_value_as_string]
> >> (0x0080): More than one value found.
> >> (Tue Jan  6 22:33:08 2015) [sssd[be[default]]]
> >> [sdap_set_config_options_with_rootdse] (0x0020): get_naming_context failed.
> >> (Tue Jan  6 22:33:14 2015) [sssd[be[default]]] [get_single_value_as_string]
> >> (0x0080): More than one value found.
> > 
> > This is weird as well, here SSSD is complaining that defaultNamingContext
> > attribute of rootDSE contains multiple values. But I don't see SSSD grabbing
> > the rootDSE anywhere at all..what log level did you use?
> 
> Log level 3
> 
> > 
> > You can read the rootDSE manually using:
> > ldapsearch -x -H ldap://server.com -s base -b "" defaultNamingContext
> 
> # extended LDIF
> #
> # LDAPv3
> # base <> with scope baseObject
> # filter: (objectclass=*)
> # requesting: defaultNamingContext
> #
> 
> #
> dn:
> 
> # search result
> search: 2
> result: 0 Success
> 
> # numResponses: 2
> # numEntries: 1
> 
> I've now added a defaultnamingcontext.
> 

Did it cause any difference? 

I wouldn't expect a missing defaultNamingContext to be fatal for SSSD..


More information about the sssd-users mailing list