You have to remember that if the AR Server is looking for the FQDN, then you
have to remember how the TCP packet will travel to get to that address. E.g.
If its not in the local host of the AR server (which I recommend as well as
having an IP-Name: FQDN in the ar.conf) then the packet could route out to
front end side of the firewall and thus get rejected.

I add the AR Servers and the front end address of the firewall to DNS for
the client, but I also add the same details to the local host of the AR
servers.

Kind regards
Danny Kellett

-----Original Message-----
From: Action Request System discussion list(ARSList)
[mailto:arsl...@arslist.org] On Behalf Of strauss
Sent: 11 November 2010 19:56
To: arslist@ARSLIST.ORG
Subject: Re: DNS entry for Server Group

I never got the apps to install properly - ITSM 7.6.03 refused to install in
a server group environment, even with the admin server that I was installing
on taken out of the group.  As a result I never even got to try the SRM,
RKM, and SLM installations.  I just finished bring the same server up
completely with all apps in standalone mode - the cleanest install I've had
lately except for RKM, and am debating just adding servers to the same db
(no server group).  I _might_ try to build a server group on the complete
stack, but with the expectation that server groups are a black hole that you
can pour time and energy into without ever finding the bottom.  Needless to
say, I am not impressed.  It's no accident that there are dozens of KB
articles on 7.x server group problems, and they are not exhaustive of the
issues (nor always in agreement on the solutions).

BTW, one lesson learned (now that you have to install FTS to support RKM) is
that the ARS installer adds FTS to the ar.cfg incorrectly using the FQDN:
Server-Plugin-Alias: ARSYS.ARF.FTS ARSYS.ARF.FTS
servername.domain.unt.edu:9998
You won't notice it until you try to index something (we've never had FTS
before, plus this is a brand new one in 7.6.03, so we would never have
noticed), OR until you try to install RKM 7.6.03.
It has to be changed to:
Server-Plugin-Alias: ARSYS.ARF.FTS ARSYS.ARF.FTS servername:9998
...preferably before the install.  During my RKM install, it generated
177,000 error entries in the arerror.log when I didn't change it, but left
it as installed by ARS 7.6.03 with the FQDN.

Most of the errors that I have encountered in the server group testing
involved plugin errors, and of course a lot of the plugins were converted
from C to java in 7.6.03 so I don't expect them to work as reliably as they
once did, anyway.  The installers - ARS, Atrium, and the apps - like to
switch between short server name and FQDN in how they define the
Server-Plugin-Aliases, and I think that is a _major_ part of the problem,
which becomes a fatal error in a server group.  Until BMC sorts this out
completely - and DOCUMENTS it, it may be more trouble than it's worth.

The only people who have responded to me with information that are actually
using server groups successfully (after numerous support tickets and changes
to the ar.cfg/conf file) are on 7.5.00.006 or earlier, not 7.6.03.  I cannot
recommend 7.6.03 for server groups (yet;...ever??) without more testing than
I probably have time for.  It is more important to me to migrate to the
7.6.03 apps than to get server groups working, so I will not re-visit a
7.5/7.6.00 implementation, but will probably limit myself to having multiple
servers on the same db.  You may find 7.5 a safer route, since it sounds
like a lot of sites (on arslist) have successfully upgraded their AR servers
to 7.5 underneath the 7.0.x (or custom) applications.

Christopher Strauss, Ph.D.
Call Tracking Administration Manager
University of North Texas Computing & IT Center
http://itsm.unt.edu/

-----Original Message-----
From: Action Request System discussion list(ARSList)
[mailto:arsl...@arslist.org] On Behalf Of Murnane, Phil
Sent: Thursday, November 11, 2010 1:07 PM
To: arslist@ARSLIST.ORG
Subject: Re: DNS entry for Server Group

Christopher:

Did you ever get you 7.6.03 server group to fail over properly?  I have a
customer that's planning to update their 7.1 ARS server groups, and we're
trying to figure out whether 7.5 or 7.6 is best for now.

Thanks!
--Phil

-----Original Message-----
From: Action Request System discussion list(ARSList)
[mailto:arsl...@arslist.org] On Behalf Of strauss
Sent: Monday, November 01, 2010 17:57
To: arslist@ARSLIST.ORG
Subject: Re: DNS entry for Server Group

Off-list hints led me to add an "A" record in the Active Directory DNS in my
forest for each IP address - the admin server and the member server - for
the common server name alias.  That name does not need to be added to campus
DNS since it is only used by the servers to communicate amongst themselves.

Today I started trying to test fail over of things like the mail system or
the entire AR system, with no success at all.  The mail server on the
failover AR server never picks up the work - it remains suspended when the
admin server mail service is shut down.  It also remains suspended when I
shut the entire admin server down, and in fact does not take over as the
admin server - it starts crashing the armonitor and ar service constantly,
with an ARERR - 90 against its own server name.  When I rebooted the member
server without the admin server running, the ar monitor crashed a half dozen
times complete with a popup faulting error.  When I rebooted both of them
(after updating the hosts file on each with a pointer to the shortname of
the server and the server group alias) they both either pop up application
fault errors or crash continuously in the arerror.log or report
unavailability of the FTS Plugin.  Impressive.

Since I have followed the server group configuration docs to the letter in
almost every section (did not config Alerts), I am becoming convinced that
server groups in 7.6.03 are completely dead on arrival.  Depending on which
server reboots first, one will constantly crash the arserver.exe, and the
other will spit out plugin server errors or FTS plugin errors or both, and
errors about not being able to connect to its own local AR Server (the ARERR
90's).  There are no apps on this lash-up, just the two AR Servers, and they
are behaving so badly today that I'm just going to shut them down.  I'll
open a ticket to support and give them a shot at the log files before
abandoning the entire concept (of server groups).

Christopher Strauss, Ph.D.
Call Tracking Administration Manager
University of North Texas Computing & IT Center
http://itsm.unt.edu/

-----Original Message-----
From: Action Request System discussion list(ARSList)
[mailto:arsl...@arslist.org] On Behalf Of Murnane, Phil
Sent: Thursday, October 28, 2010 4:00 PM
To: arslist@ARSLIST.ORG
Subject: Re: DNS entry for Server Group

Funny you should mention this Christopher, I just had to do the same thing
for a client.  It seems the normal configuration is to point all ARS clients
(user tool, mid-tier, API, etc) to the load balancer alias name, which is
also the name of the server group.  The load balancer then does its job and
spreads the load among the group member servers.  Since each member of the
group knows the load balancer alias as itself, it doesn't really matter
which server handles any given transaction (speaking generally, in practice
there are "sticky" session matters to deal with).  So what to do if you're
not using a load balancer?

We followed the instructions in the AR System guide for managing server
groups and then added one additional step of our own -- for each host that
will run an ARS client, we manually updated the hosts file to resolve the
server group name to one of the group member server's IP address.  We
estimated the load each client would generate, and tried to balance that
load across the member servers.  Of course if a client is running on a
member server, then it's efficient to have the server group name resolve to
127.0.0.1 (or the equivalent).  It's important to note that all clients are
configured with server name = group name except for admin class clients, who
always have server name = admin server name.

HTH,
--Phil

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