Saturday, May 29, 2010

vSphere Tips and Tricks Part 1

Disclaimer: Ensure these changes have been thoroughly tested and confirmed with VMware support prior to rolling out into production. Most of these changes and tips may be undocumented by VMware, test at your own risk!

Map Service Console/COS VMDK to specific ESX host (useful if you boot from SAN):
grep -i "hostname" /vmfs/volumes/[datastore]/[esxconsole-datastore-uuid]/logs/sysboot-vmkernel-late.log

[root@everest ~]# grep -i "hostname" /vmfs/volumes/everest-local-storage/esxconsole-49a095a4-204d-c7ba-9bb8-001f29c7b048/logs/sysboot-vmkernel-late.log

0:00:00:06.289 cpu1:4105)Config: 363: "HostName" = "everest.primp-industries.com", Old value: "localhost" (Status: 0x0)


Retrieve VmId from vmware-cmd similiar to that in vimsh/vmware-vim-cmd (only available on classic ESX, not sure why it's not in vCLI):
vmware-cmd /vmfs/volumes/[datastore]/[path_to_vm]/vm.vmx getid

[root@everest ~]# vmware-cmd /vmfs/volumes/d32c5a97-e039bdbf/vCenter-ESX4.02172009/vCenter-ESX4.02172009.vmx getid
getid() = 32


VMware FT statistics and debugging utility
Available after some patch set, generally 4.0u1+

[root@esx-5 ~]# ft-stats
Usage: ft-stats [-hvf] [-c ] [-l] [-n ] [-d ] [-s ] [-w ]
-h, --help Show this message
-v, --verbose verbose output
-f, --force Continue even if version check fails
-c, --cache Use VSI cache file
-l, --list list FT VMs
-n, --iterations Print stats for n iterations
-d, --delay Print stats every n secs (default:5)
-s, --snapshot Collect stats for n secs
-w, --world Print stats for worldID

Note: This tool is intended to assist in troubleshooting and should only be used
with direction by VMware support. All other use of this tool is unsupported.


esxupdate - Query for installed/retired packages with undocumented "--vib-view" option
esxupdate --vib-view query

[root@himalaya ~]# esxupdate --vib-view query
--------------------------------------VIB ID------------------------------------- Package State -----------Timestamp------------
rpm_vmware-esx-drivers-scsi-fnic_400.1.1.0.109.2vmw-2vmw.1.9.208167@x86_64 installed 2010-01-06T12:24:38.100201-05:00
rpm_acpid_1.0.4-9.el5_4.2@x86_64 installed 2010-04-02T17:09:44.566014+00:00
rpm_samba-client_3.0.33-3.15.el5_4.1@x86_64 installed 2010-04-02T17:09:44.171847+00:00
rpm_nss_3.12.3.99.3-1.2157.vmw@x86_64 installed 2010-04-02T17:09:41.148547+00:00
rpm_initscripts_8.45.19.EL-1.2442.vmw@x86_64 installed 2010-04-02T17:09:36.911452+00:00


Change default COW (copy on write) disk growth value
Query (Default is 16MB):

[root@himalaya ~]# esxcfg-advcfg -g /COW/COWDiskSizeIncrement
Value of COWDiskSizeIncrement is 32768


Set (e.g. 256MB):

[root@himalaya ~]# esxcfg-advcfg -s 524288 /COW/COWDiskSizeIncrement
Value of COWDiskSizeIncrement is 524288


The input value for changing COWDiskSizeIncrement is in sectors

UNIT SECTORSCOW GROWTH SIZE
3276816MB
6553632MB
13107264MB
262144128MB
524288256MB
20971521024MB
........

Easy formula is (SIZE_IN_MB)*(1024)*(2) = SECTOR VALUE

3 comments:

  1. William, is the COW value only stand for snapshot ?

    ReplyDelete
  2. @NiTRO,

    This applies to snapshots and thinly provisioned disks, basically any "sparse" disks will be using the default COW value of 16MB as I understand it.

    Here are more details regarding COW disks - http://kb.vmware.com/Platform/Publishing/attachments/1001175_fLinked%20Clone%20Managment.htm

    ReplyDelete
  3. How to use ft-stats ?
    Log = Stats not available, FT probably not active
    GL

    ReplyDelete