Wu's Blog

My SMVI backup job was crashed few days ago, the stupid application generated a lot of snapshots for virtual machine!!! It's  hundred! I really don't like to remove one by one! That's what I used to clean up the snapshot. Get-VM | Get-Snapshot -Name smvi* | Remove-Snapshot I used wildcard smiv* , it means all snapshot that name start with smvi .

You probably see this rare problem: your storage team allocate new lun to esxi 5.0 host, lun is visible in add new storage screen, but invisible in extend datastore  screen. Add new storage screen: Increase datastore capacity:   That's because the datastore, lun is connected to multiple esxi / esx host which have different version, please be sure storage is connected to same version of esxi / esx host.

You may see the keyword ALUA frequently if you read VMware storage documents, so what’s the ALUA exactly is? How it reflects in ESXi 5.0? What’s the advantage of ALUA? I certainly have the questions, you? First of all, ALUA is short word of “Asymmetric Logic Unit Access”, you probably already knowJ, ALUA is a SCSI standard, it’s not support by all storage arrays, but I think most large company should have the ALUA supported array. There are different articles tried to explain what ALUA is, I’m not a storage expert, I just want to give my interpretation. You may don’t agree, have question about that, please give me a comment, I’m willing to talk about that. Generally, storage array ( Active-Active ) have two controllers (SPA, SPB), each controller have two paths (SPA0, SPA1, SPB0, SPB1), data transmits between ESX and storage array through these paths, in older ESX version, it can only use FIXED path selection policy to transmit data through a single path. Here is a potential problem, f

vSphere client pop following error when I put some ESXi 5.0 host to maintenance mode. A general system error occurred. Invalid fault That message really no help for troubleshooting, I found a KB article in VMware website, but it's not my case. My virtual machines is intact, I can change setting, remove from inventory or power on/off the boxes, so what's the issue? I found the following message in hostd.log: 2013-01-18T01:18:10.177Z [39489B90 info 'Default' opID=DDBEEEE7-0000023A-78] File path provided /vmfs/volumes/4fef9740-0b0c0cee-c1a4-e8393521ff62/VM-01 does not exist or underlying datastore is inaccessible: /vmfs/volumes/4fef9740-0b0c0cee-c1a4-e8393521ff62/VM-01 Also found messages in vmware.log: 2013-01-18T01:19:41.966Z| vmx| Migrate_SetFailure: Timed out waiting for migration start request. The logs indicates ESXi cannot identify the location of VM configuration file, it leads to ESXi don't know the IP address family of VM and also not able to allocate      m

When I tried to apply my host profile to a ESXi 5.0 host, it's show me " There is no valid reference host associated with the profile ". I was thinking it's probably caused by answer file, but actually it's due to reference host lost in host profile! I made simple question too complicate...:-)

The installer may prompt " Failed to established connection " after input SQL database information. Reason can be vary. If your SQL account password is correct, it maybe caused by SQL password policy. The three password policy is selected by default when you create SQL account. You could also find similiar error message in %TEMP%/vm-sso-javalib.log : [2013-01-11 10:54:33,640]ERROR 733[main] - com.vmware.vim.installer.core.logging.CoreLoggerImpl.error(?:?) - Failed to established connection: com.microsoft.sqlserver.jdbc.SQLServerException: Login failed for user 'vCenterSSO_DBA'.  Reason: The password of the account must be changed. Please deselect the 3 password policy or change your SQL password more complexitily.  

We are moving virtual machine from old storage to new datastore today, there are a lot of old datastores need to be removed after migration, for saftey consideration, I move all old datastore to a folder and then do decommission process. There are more than 60 datastores, and vSphere client not allow move in one time. Here is a PowerCLI script can help move multiple datastores to a folder. Note: Please make sure your folder name is uniquely. When you create datastores.txt, please make sure first line is "Name", one datastore name in each line. Example: Name datastore1 datastore2 datastore3 ... Move-Datastores

A lot of storage support hardware acceleration, it is able to offload some storage operation from ESXi 5.x host to storage filer, the feature can significantly improve performance during cloning, vMotion, coping...etc. Different storage device may support different features of hardware acceleration, block device have block zero , full copy , hardware assisted locking , thin provisioning,  NAS device have  extended stats, file cloning, large scale native SS, native SS to LC, space reserve. You can find the detail information in this article . For block storage, we initially create VMFS5 datastore by one LUN, more LUN (extent) maybe added to the datastore when free space is low. Please be sure that all extent of VMFS5 datastore should have same ATS feature, support or not. You may see a error message " Operation failed, unable to add extent to filesystem"  when you add a non-ATS extent to ATS enabled VMFS5 datastore. How to know if lun support ATS? You can login ESXi 5.x host v

Guest OS of virtual machine can synchronize time by several way, such as NTP, VMware Tools, Windows Time Service, CMOS...etc. VMware Tools synchronize time with ESXi host when  you enable periodic time synchronization. VMware Tools time synchronization function is disabled by default, but that's doesn't means time synch never happens between guest OS and host. It still happens after certain operations: When the VMware Tools daemon is started. When resuming a VM from suspended status. After reverting from a snapshot. After shrinking a disk. It can causes some problem if guest OS have different time with host, it can lead to SAP application failed due to SAP database timestamp different with guest OS. You can completely disable the time synchronization by following step: Power off the VM. Add following lines to .vmx file. tools.syncTime = "FALSE" time.synchronize.continue = "FALSE" time.synchronize.restore = "FALSE" time.synchronize.resum

Wordpress.com is blocked by China government, it's not the best choice for me from high available perspective :-) But as you may know, Wordpress is the best blog application in the planet, I don't know any other blog can be so perfect! I have to use it even so it's blocked. I'm writing this article via VPN, I think IT person in China whom familiar with English should have VPN to check Google and technical website, hence it's should be no issue for them to access my blog.