Monthly Archive: May 2012

May 17

Why is my pathing policy limited to “fixed” or “MRU” with things like MSCS cluster?

by

May 17, 2012

Yesterday I received an email from someone. He wanted to know why he was limited to using either the “fixed” or “MRU” pathing policy for the LUNs attached to his MSCS cluster. In his environment they used round-robin for everything and not being able to configure all of them with the same policy was against their internal policy. The thing is that if round-robin would be used and the path would switch (by default every 1000 I/Os) the SCSI-2 reservation would need to be re-acquired on this LUN. (MSCS uses SCSI-2 reservations for their cluster devices) As you can imagine that could cause a lot of stress on your array and could lead to all sorts of problems. So please do not ignore this recommendation! Some extra details can be found in the following KB articles:

“Why is my pathing policy limited to “fixed” or “MRU” with things like MSCS cluster?” originally appeared on Yellow-Bricks.com. Follow us on Twitter and Facebook.
Available now: vSphere 5 Clustering Deepdive. (paper | e-book)

Tags: ,

Permanent link to this article: http://www.startswithv.com/2012/05/17/why-is-my-pathing-policy-limited-to-fixed-or-mru-with-things-like-mscs-cluster/

May 16

KB article about SvMotion / VDS / HA problem republished with script to mitigate!

by

May 16, 2012

Just a second ago the GSS/KB team republished the KB article that explain the vSphere 5.0 problem around SvMotion / vDS / HA. I wrote about this problem various times and would like to refer to that for more details. What I want to point out here though is that the KB article now has a script attached which will help preventing problems until a full fixed is released. This script is basically the script that William Lam wrote, but it has been fully tested and vetted by VMware. For those running vSphere 5.0 and using SvMotion on VMs attached to distributed switches I urge you to use the script. I expect that the PowerCLI version will also be attached soon.

http://kb.vmware.com/kb/2013639

“KB article about SvMotion / VDS / HA problem republished with script to mitigate!” originally appeared on Yellow-Bricks.com. Follow us on Twitter and Facebook.
Available now: vSphere 5 Clustering Deepdive. (paper | e-book)

Tags: , ,

Permanent link to this article: http://www.startswithv.com/2012/05/16/kb-article-about-svmotion-vds-ha-problem-republished-with-script-to-mitigate/

May 10

vCenter Infrastructure Navigator throws the error: “an unknown discovery error has occurred”

by

May 10, 2012

I was deploying vCenter Infrastructure Navigator (VIN) in my lab today and the following error came up after I wanted to check dependencies for a virtual machine:

Access failed, an unknown discovery error has occurred

I rebooted several services but nothing seemed to solve it. Internally I bumped on a thread which had the fix for this problem: DNS. Yes I know always DNS right. Anyway, I used “DHCP” for my VIN appliance and this DHCP server pointed to a DNS server which did not have the IP/name of my ESXi hosts listed. Because of this the discovery didn’t work as VIN tries to resolve the names of the hosts as they were added to vCenter Server. I configured VIN with a fixed IP and pointed the VIN appliance to the right DNS server. Problem solved.

“vCenter Infrastructure Navigator throws the error: “an unknown discovery error has occurred”” originally appeared on Yellow-Bricks.com. Follow us on Twitter and Facebook.
Available now: vSphere 5 Clustering Deepdive. (paper | e-book)

Tags: ,

Permanent link to this article: http://www.startswithv.com/2012/05/10/vcenter-infrastructure-navigator-throws-the-error-an-unknown-discovery-error-has-occurred/

Older posts «

» Newer posts