"I'm not sure that an ACL would do the trick though, probably would just show 
up in the traces as a time out"

Exactly. The Publisher will simply failover to the next LDAP server in the list 
if it cannot establish a connection within 5-seconds to the primary LDAP 
server. Regardless, the node receiving the LDAP-user authentication request 
will source the authentication attempt over Tomcat itself. So if a user browses 
to the /ccmuser page on a subscriber01 and attempts to authenticate, the 
authentication request should not be passed to subscriber02 or the publisher - 
it should be handled by that node itself. I doubt this behavior changes with a 
properly configured LDAPS cluster but I can be wrong. I'm not as familiar with 
the authentication process for LDAPS.

It also depends on what platform the authentication request is coming from. 
Using UCCX as an example again, it sends user authentication to CUCM via AXL 
API. So successful authentication from there is dependent on the AXL server 
assignments in UCCX - the AXL server (whatever node that might be) receiving 
the request should use Tomcat to source the LDAP authentication request. 
However, even with successful LDAP authentication on a subscriber, agent logins 
can of course still fail on the JTAPI/CTI side for other reasons, especially if 
AXL and CTI server assignments are different.

@Ryan: For the two lab failures, I'm wondering if this was a pre-existing 
condition that's unrelated to the test itself.

As for the login failures during the 4-hour window, I can think of a few 
reasons off the top of my head. Are the LDAP server entered as FQDN or IP 
addresses? If FQDN, are all your CUCM nodes configured with the same DNS 
servers? Not that it's a requirement, but if you're using different DNS server 
assignments, I would make sure the Subs can resolve the name. If using IP 
address, can you reach the secondary LDAP server from the Subscriber with no 
issues? Are the port assignments correct for your list of LDAP servers in CUCM? 
As in... if you're using port 3268 across the board for all added LDAP servers 
in CUCM, and the secondary LDAP server is not a Global Catalog, I can see this 
potentially causing a failure when the primary LDAP server is offline. Another 
thing that comes to mind which I twice ran into is CSCub71123, but this should 
be resolved in 10.0 and up so you should be good. I'm just thinking as I type 
here but Tomcat Security logs off the node receiving the auth request should 
reveal more concrete information... but keep in mind the issue can exist 
earlier in the auth process and might not even be reaching Tomcat. Grab them 
off your cluster via RTMT and take a quick look - they're very easy to 
decipher... very straight forward log files IMO.

Hope this helps.

- Dan



From: cisco-voip [mailto:[email protected]] On Behalf Of 
Matthew Collins
Sent: Monday, July 06, 2015 11:24 AM
To: Ryan Huff; Lelio Fulgenzi
Cc: [email protected]
Subject: Re: [cisco-voip] LDAP Authentication when CUCM publisher is down.

Thanks for all your responses.

In our scenario when we lost one of a DC (planned maintenance) that hosted the 
CUCM, IM&P, and UCCX Pubs UCCX fineness agents were unable to log in. Had to 
resort to a couple of local back up agent accounts.

LDAP authentication wasn't working for any service (Jabber, CUCM Web Gui, UCCX 
Finesse Web Gui). I wasn't around to do any testing and as it was only a 4 
hours maintenance period it wasn't logged with us and no logs where collected.



Regards

Matthew Collins


From: cisco-voip [mailto:[email protected]] On Behalf Of Ryan 
Huff
Sent: 06 July 2015 15:24
To: Lelio Fulgenzi
Cc: [email protected]<mailto:[email protected]>
Subject: Re: [cisco-voip] LDAP Authentication when CUCM publisher is down.

I'll be interested to hear your results if you try!

I'm not sure that an ACL would do the trick though, probably would just show up 
in the traces as a time out. You'd probably have to stop the tomcat service on 
the pub (something to tell the cluster not to try and use the PUB as a bind 
source), which is pretty destructive on the pub in a working production 
environment (disclaimer: I do not advocate you do that).


________________________________
Subject: Re: [cisco-voip] LDAP Authentication when CUCM publisher is down.
From: [email protected]<mailto:[email protected]>
Date: Mon, 6 Jul 2015 10:12:53 -0400
To: [email protected]<mailto:[email protected]>
CC: [email protected]<mailto:[email protected]>; 
[email protected]<mailto:[email protected]>
The worst case scenario, which we ran into, was a scenario where the pub is up 
and accepting auth requests but not able to process them. In our case the 
cluster was up for almost 300 days, and there were memory error alerts popping 
up. It would be nice for the system to understand this issue and go to the next 
node to try the auth process.

Interesting note about LDAPS. We are using that. Not sure if that poses 
additional issues.

Wish there was an easy way to test this out in production. Perhaps a quick ACL 
to block phone agent and desktop agent access to the pub and see what happens. 
And then another test where the ACL blocks access to the LDAP server 
temporarily.

Sent from my iPhone

On Jul 6, 2015, at 10:04 AM, Ryan Huff 
<[email protected]<mailto:[email protected]>> wrote:
Hi Dan!

Thanks for the clarification/correction .... I just happen to have a few 3-node 
cluster hanging around and I just tried this 5 times in a mix of 9.1.1, 10.0 
and 10.5 and here is what I found:

3 times LDAP auth was a seamless failover to the sub
2 times LDAP auth did not work on the sub until I bounced the tomcat service on 
the sub, then it worked fine.

I'm wondering if that, on the times it doesn't work in a failover (because I 
have experienced it a few times) a simple service bounce is all that is needed?

I suppose another cause of LDAP auth failover NOT working (but not always 
intuitive) would be cluster over wan (nodes in the cluster are not all on the 
same segment) and the sub node that LDAP auth is trying to bind from can't talk 
to the AD server.
________________________________
From: [email protected]<mailto:[email protected]>
To: [email protected]<mailto:[email protected]>; 
[email protected]<mailto:[email protected]>
Date: Mon, 6 Jul 2015 13:45:08 +0000
Subject: Re: [cisco-voip] LDAP Authentication when CUCM publisher is down.
LDAP authentication is used by Tomcat and isn't just restricted to the 
Publisher server - Subscriber nodes handle this as well. DirSync is specific to 
synchronization of LDAP attributes and only runs on the Pub, so synchronization 
would definitely be affected if the Publisher is offline. I suggest to check 
out the Tomcat Security logs off CUCM for more info on user authentication 
against LDAP and your source of failure.

So to answer your question, LDAP authentication should still work when the 
Publisher is offline.

For the UCCX agent concern, authentication of agents occur over AXL to CUCM, so 
if the AXL server is the Publisher, and that's offline or experiencing issue w/ 
Tomcat during an authentication attempt by the UCCX agent, then I would imagine 
seeing a failure. AXL and Tomcat Security logs off the UCM side should shed 
some light on that problem

As for SSO, I checked w/ my teammate and, in his experience, SSO can be handled 
by Subscriber nodes assuming the metadata was imported to those servers - 
authentication occurs against the IdP and not CUCM so this seems logical to me 
as well.

Hope this helps.

- Dan


From: cisco-voip [mailto:[email protected]] On Behalf Of Lelio 
Fulgenzi
Sent: Monday, July 06, 2015 9:16 AM
To: [email protected]<mailto:[email protected]>
Subject: Re: [cisco-voip] LDAP Authentication when CUCM publisher is down.


This has been our experience as well. Glad you started this thread. It's seems 
like a huge single point of failure to me for such an integral part of the 
process. I suspect hunt group login would also be affected.

Sent from my iPhone

On Jul 6, 2015, at 5:02 AM, Matthew Collins 
<[email protected]<mailto:[email protected]>> wrote:
Hi All,

CUCM 10.5

Just trying to get some conformation, When LDAP Synchronization and 
authentication is enabled this is performed by the DirSync process that only 
runs on the CUCM Publisher. So If we lose the CUCM Publisher for whatever 
reason it would seem that the Authentication also fails due to the single point 
of failure of DirSync. Should LDAP authentication still work if the CUCM 
Publisher is still down.

So for LDAP users this would stop them signing in to Jabber clients and UCCX 
agents who are ldap'ed synced logging into the finesse webpages. Does anyone 
know is SSO is resilient on the CUCM publisher or would SSO still work in a 
Publisher outage.

Regards

Matthew Collins

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