V-IT, I AM GOING THROUGH IT

HP SIM to monitor ESX hosts

eagleh — Thu, 19 Jun 2008 19:34:00 GMT

1> create HP CMS (Center Management Server) and install HP SIM (System Inside Manager) 5.2 on it.
2> install HP Insight Management Agent 8.0 on ESX host http://virtrix.blogspot.com/2006/09/hp-insight-manager-agents-for-vmware.html

HP SIM did detecte both ESX hosts. However, it shows "degraded or failed" under "Health Status" column in SIM even though there are not.

log on ESX, run "server hpadm configure" did the trick.

This is my working /etc/snmpd/snmpd.conf:

rwcommunity mycomstring 127.0.0.1
rocommunity mycomstring 127.0.0.1
rwcommunity mycomstring hpcms.mydomain.mag
rocommunity mycomstring hpcms.mydomain.mag
trapcommunity mycomstring
trapsink 192.168.14.19 mycomstring {I bet "trapsink hpcms.mydomain.mag public" will work too.}

Different guest OS VMs on different datastore(LUN)?

eagleh — Thu, 29 May 2008 14:04:00 GMT

"It is not a best practice to isloate different OS on different LUNS. VMware has always encouraged load mixing. Avoid mixing virtual machines that have competing resource requirements. The most important is not too have too many I/O intensive VMs on one LUN. I always try to stay under 25VMs per LUN. " --dmismash

Vmotion vs. Storage Vmotion

eagleh — Wed, 28 May 2008 17:25:00 GMT

Vmotion moves a running VM from one host to another. (VC Client GUI, means by "Migrate...")

SVmotion moves a running VM (files belong to that VM) from one vmfs storage to another. (have to be done through CLI. No VMware supported GUI so far.)

Both should not inturrupt VM. VMs can be up and running during the process.
Note: If you can power off the VM, you can use VC Client GUI ("Migrate") to move both!

The most famous Third-Party GUI tool (a VI Client plug-in) for S-Vmotion recognized by VMWare is developled by Andrew Kutz: http://communities.vmware.com/thread/126141

How many VMs per LUN?

eagleh — Wed, 28 May 2008 16:53:00 GMT

"While VMware Infrastructure 3 supports up to 100 VMs per LUN, 32 VMs per LUN may often be acceptable. However, HP recommends being more conservative and using 8 - 10 VMs per LUN. In a NAS or iSCSI environment, HP recommends using 8 - 16 VMs per LUN."

About VCB

eagleh — Wed, 28 May 2008 16:29:00 GMT

The beauty of VCB is "LAN-Free", which eliminats the traditional backup window. You can back up your machine whenever you want, in theory. Also, yous ycan do image level backup which enables you to restore it in no time. With huge RDMs attached, the VM being backed up through VCB is becoming impossible (limit space on VCB Proxy) and the worst senario happened to me, the VM hung up and left LUNs unaccessible. (Big time!)

Eventually I put all my RDMs to "Independent Virtual Compatibility" mode, therefore VCB will skip those RDMs automatically and back up OS part only. Then I use regular DP agent to backup data part (RDMs), of course nightly.

Note: DP6.0 doesn't support VCB1.1, yet as I am writing this post.

System CPU usage spikes to 100%

eagleh — Wed, 28 May 2008 15:31:00 GMT

This is an ongoing issue that bothers me from time to time since our VMware Infrastructure in production. There could be quiet a few reasons cause this problem. Everytime it spikes, the whole machine is rendered useless. I have done:

1> Applied ESX3.5 Update 1 and VirtualCenter 2.5 Update 1 (This CPU problem has been fixed for a while, however, it came back recently.)
2> I am holding off the April-30-2008 patch because people are saying it brought back the CPU problem which Update 1 had fixed.
3> I switch DRS from Partially Automatic to Manually. So there should not be any Vmotion happened until next patch for this CPU issue. I have observed that Vmotion could be one reason to trigger this High CPU issue.
4> However, yesterday, it happened right at 5PM (without any Vmotion). So I guess it has to be something scheduled to run at 5PM. Eventually I realized MS System Center Essential Agent was installed on this VM. uhha! It was a left-over. Uninstalled it and hopefully that was it.

This issue has been driving me NUTS!

RDM or VMFS disk?

eagleh — Wed, 28 May 2008 15:16:00 GMT

I found RDM is flexiable. You can hook it up with a physical machine down to the road if in need. Somebody reported RDM could be faster than VMFS. Also, RDMs are right allocated from SAN, therefore they are easier to grow (up to 2T). For my situation, we have such quite a few big data storage (2T, 1T, 600G, ) for the file server, I am afraid it's not a good idea to make such big VMFS disks.