LISTSERV mailing list manager LISTSERV 16.0

Help for OUTAGE Archives


OUTAGE Archives

OUTAGE Archives


OUTAGE@LISTS.IPHOUSE.NET


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Proportional Font

LISTSERV Archives

LISTSERV Archives

OUTAGE Home

OUTAGE Home

OUTAGE  October 2010

OUTAGE October 2010

Subject:

Load balancer failover occurred

From:

Mike Horwath <[log in to unmask]>

Reply-To:

[log in to unmask]

Date:

Sat, 30 Oct 2010 13:05:02 -0500

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (61 lines)

Ethernet links went down:	Sat Oct 30 12:33:22 CDT 2010
Ethernet links came up:		Sat Oct 30 12:33:58 CDT 2010

This caused the active load balancer to drop and the standby unit to
take over, then 36 seconds later, it cut back.

The normally standby servers' ethernet links were unaffected during
this though both load balancers are plugged into the same physical
switches on adjacent ports.  This is pointing to a problem on the
normally active load balancer and I'll need to do more log searching
to check on potential permanent failure.

Summary: All services handled on our cluster are back online

Techno-babble starts here...

The cutover from active to standby to active caused the servers behind
the load balancers to cache the ARP (address resolution protocol)
address for the gateway for the servers for the now-standby unit.

I know that sounds confusing, sorry!

To help explain:

   gateway is on 192.168.x.254 xx:xx:xx:xx:xx:17 (normal active unit)
   failure
   gateway is on 192.168.x.254 xy:xy:xy:xy:xy:4a (normal standby unit)
   cutback
   gateway is on 192.168.x.254 xx:xx:xx:xx:xx:17 (normal active unit)

but the systems cached the ..:4a address as it had changed and would
not recheck until after expiration.  This is a completely normal and
desired behaviour.

Oct 30 12:33:31 web-10 kernel: arp: 192.168.x.254 moved from xx:xx:xx:xx:xx:17 to xy:xy:xy:xy:xy:4a on em0

I had to log into each of the servers and clear the ARP cache for the
gateway address and everything came back online.

Web services and mail services handled on our cluster were affected
during this event.

All services are back online, the outage lasted approximately 15
minutes while I logged into each and every server.  During this time
some of the servers had already updated their ARP cache, so the
different services were back online faster than the time it took me to
log into all of the servers.

I find no errors on services at this time and everything looks good.

Now starts the investigation into why the normally active load
balancer thought that *all* of its ethernet ports went down at
precisely the same moment.

Support can be reached Monday thru Friday from 8:00am until 8:00pm via
phone at 612-337-6340, or via email at [log in to unmask]

-- 
Mike Horwath      ipHouse - Welcome home!       [log in to unmask]
        The universe is an island, surrounded by whatever it is
        that surrounds universes. - Berkeley Fortune

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

August 2020
May 2020
April 2020
January 2020
November 2019
October 2019
October 2018
August 2018
July 2018
May 2018
April 2018
February 2018
January 2018
November 2017
October 2017
August 2017
July 2017
May 2017
April 2017
February 2017
January 2017
December 2016
November 2016
October 2016
September 2016
August 2016
July 2016
June 2016
April 2016
December 2015
November 2015
October 2015
September 2015
August 2015
July 2015
June 2015
May 2015
April 2015
March 2015
January 2015
December 2014
November 2014
October 2014
September 2014
August 2014
May 2014
April 2014
March 2014
January 2014
December 2013
November 2013
July 2013
June 2013
May 2013
April 2013
February 2013
January 2013
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
October 2011
September 2011
July 2011
June 2011
March 2011
February 2011
January 2011
November 2010
October 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
2008
2007
2006
December 2005
November 2005
October 2005
September 2005
August 2005
July 2005
June 2005
May 2005
April 2005
March 2005
February 2005
January 2005
December 2004
November 2004
October 2004

ATOM RSS1 RSS2



LISTS.IPHOUSE.NET

CataList Email List Search Powered by the LISTSERV Email List Manager