Technologist

One of the most important things you should do to your systems is to ensure they have the right time.
In this post I will show how to check and ensure your systems have the correct time using PowerCli.

==> Login to vCenter:

$admin = Get-Credential –Credential EXAMPLE\john
Connect-VIServer -Server vc.example.com -Credential $admin

==> Check time settings:

Get-VMHost | Sort Name | Select Name, `
   @{N="NTPServer";E={$_ |Get-VMHostNtpServer}}, `
   Timezone, `
   @{N="CurrentTime";E={(Get-View $_.ExtensionData.ConfigManager.DateTimeSystem) | Foreach {$_.QueryDateTime().ToLocalTime()}}}, `
   @{N="ServiceRunning";E={(Get-VmHostService -VMHost $_ |Where-Object {$_.key-eq "ntpd"}).Running}}, `
   @{N="StartUpPolicy";E={(Get-VMHostService -VMHost $_ |Where-Object {$_.Key -eq "ntpd"}).Policy}}, `
   @{N="FirewallException";E={$_ | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Select-Object –ExpandProperty Enabled}} `
   | Format-Table -AutoSize

Output:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMHost | Sort Name | Select Name, `
>>    @{N="NTPServer";E={$_ |Get-VMHostNtpServer}}, `
>>    Timezone, `
>>    @{N="CurrentTime";E={(Get-View $_.ExtensionData.ConfigManager.DateTimeSystem) | Foreach {$_.QueryDateTime().ToLocalTime()}}}, `
>>    @{N="ServiceRunning";E={(Get-VmHostService -VMHost $_ |Where-Object {$_.key-eq "ntpd"}).Running}}, `
>>    @{N="StartUpPolicy";E={(Get-VMHostService -VMHost $_ |Where-Object {$_.Key -eq "ntpd"}).Policy}}, `
>>    @{N="FirewallException";E={$_ | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Select-Object -ExpandProperty Enabled}} `
>>    | Format-Table -AutoSize
>>

Name                 NTPServer 					TimeZone CurrentTime         ServiceRunning StartUpPolicy FirewallException
----                 --------- 					-------- -----------         -------------- ------------- -----------------
esx1.example.com           					UTC      6/7/2015 3:25:39 PM          False off                       False
esx2.example.com           					UTC      6/7/2015 3:25:40 PM          False off                       False
esx3.example.com 	{192.168.10.1,192.168.11.1}	        UTC      6/7/2015 3:25:42 PM          False off                       False
esx4.example.com 	192.168.11.1 				UTC      6/7/2015 3:25:43 PM          False off                       False

==> Set time to correct time:

// Get time from the machine running PowerCli
$currentTime = Get-Date

// Update time on ESX hosts
$hosts_time = Get-VMHost | %{ Get-View $_.ExtensionData.ConfigManager.DateTimeSystem }
$hosts_time.UpdateDateTime((Get-Date($currentTime.ToUniversalTime()) -format u))

==> Remove old NTP servers (if any):

$old_ntp_server = '192.168.10.1'
Get-VMHost | Remove-VmHostNtpServer -NtpServer $old_ntp_server -Confirm

Output:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMHost | Sort Name | Select Name, `
>>    @{N="NTPServer";E={$_ |Get-VMHostNtpServer}}, `
>>    Timezone, `
>>    @{N="CurrentTime";E={(Get-View $_.ExtensionData.ConfigManager.DateTimeSystem) | Foreach {$_.QueryDateTime().ToLocalTime()}}}, `
>>    @{N="ServiceRunning";E={(Get-VmHostService -VMHost $_ |Where-Object {$_.key-eq "ntpd"}).Running}}, `
>>    @{N="StartUpPolicy";E={(Get-VMHostService -VMHost $_ |Where-Object {$_.Key -eq "ntpd"}).Policy}}, `
>>    @{N="FirewallException";E={$_ | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Select-Object -ExpandProperty Enabled}} `
>>    | Format-Table -AutoSize
>>

Name                 NTPServer 	TimeZone CurrentTime         ServiceRunning StartUpPolicy FirewallException
----                 --------- 	-------- -----------         -------------- ------------- -----------------
esx1.example.com           	UTC      6/7/2015 3:25:39 PM          False off                       False
esx2.example.com           	UTC      6/7/2015 3:25:40 PM          False off                       False
esx3.example.com 		UTC      6/7/2015 3:25:42 PM          False off                       False
esx4.example.com		UTC      6/7/2015 3:25:43 PM          False off                       False

==> Change NTP to desired configuration:

$ntp_server = '192.168.10.1'
Get-VMHost | Add-VMHostNtpServer $ntp_server
Get-VMHost | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Set-VMHostFirewallException -Enabled:$true
Get-VMHost | Get-VmHostService | Where-Object {$_.key -eq "ntpd"} | Start-VMHostService
Get-VMhost | Get-VmHostService | Where-Object {$_.key -eq "ntpd"} | Set-VMHostService -policy "automatic"

Output:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> $ntp_server = '192.168.10.1'
PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMHost | Add-VMHostNtpServer $ntp_server
192.168.10.1
192.168.10.1
192.168.10.1
192.168.10.1

==> Enable Firewall Exception

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMHost | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Set-VMHostFirewallException -Enabled:$true

Name                 Enabled IncomingPorts  OutgoingPorts  Protocols  ServiceRunning
----                 ------- -------------  -------------  ---------  --------------
NTP Client           True                   123            UDP        True
NTP Client           True                   123            UDP        True
NTP Client           True                   123            UDP        False
NTP Client           True                   123            UDP        False

==> Start NTPd service

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMHost | Get-VmHostService | Where-Object {$_.key -eq "ntpd"} | Start-VMHostService

Key                  Label                          Policy     Running  Required
---                  -----                          ------     -------  --------
ntpd                 NTP Daemon                     on         True     False
ntpd                 NTP Daemon                     on         True     False
ntpd                 NTP Daemon                     off        True     False
ntpd                 NTP Daemon                     off        True     False

==> Ensure NTPd service starts automatically (via policy)

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMhost | Get-VmHostService | Where-Object {$_.key -eq "ntpd"} | Set-VMHostService -policy "automatic"

Key                  Label                          Policy     Running  Required
---                  -----                          ------     -------  --------
ntpd                 NTP Daemon                     automatic  True     False
ntpd                 NTP Daemon                     automatic  True     False
ntpd                 NTP Daemon                     automatic  True     False
ntpd                 NTP Daemon                     automatic  True     False

==> Verify all is set the way you expected

Get-VMHost | Sort Name | Select Name, `
   @{N="NTPServer";E={$_ |Get-VMHostNtpServer}}, `
   Timezone, `
   @{N="CurrentTime";E={(Get-View $_.ExtensionData.ConfigManager.DateTimeSystem) | Foreach {$_.QueryDateTime().ToLocalTime()}}}, `
   @{N="ServiceRunning";E={(Get-VmHostService -VMHost $_ |Where-Object {$_.key-eq "ntpd"}).Running}}, `
   @{N="StartUpPolicy";E={(Get-VMHostService -VMHost $_ |Where-Object {$_.Key -eq "ntpd"}).Policy}}, `
   @{N="FirewallException";E={$_ | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Select-Object –ExpandProperty Enabled}} `
   | Format-Table -AutoSize

Output:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VMHost | Sort Name | Select Name, `
>>    @{N="NTPServer";E={$_ |Get-VMHostNtpServer}}, `
>>    Timezone, `
>>    @{N="CurrentTime";E={(Get-View $_.ExtensionData.ConfigManager.DateTimeSystem) | Foreach {$_.QueryDateTime().ToLocalTime()}}}, `
>>    @{N="ServiceRunning";E={(Get-VmHostService -VMHost $_ |Where-Object {$_.key-eq "ntpd"}).Running}}, `
>>    @{N="StartUpPolicy";E={(Get-VMHostService -VMHost $_ |Where-Object {$_.Key -eq "ntpd"}).Policy}}, `
>>    @{N="FirewallException";E={$_ | Get-VMHostFirewallException | where {$_.Name -eq "NTP client"} | Select-Object -ExpandProperty Enabled}} `
>>    | Format-Table -AutoSize
>>

Name                 NTPServer  TimeZone CurrentTime         ServiceRunning StartUpPolicy FirewallException
----                 ---------  -------- -----------         -------------- ------------- -----------------
esx1.example.com 192.168.10.1 UTC      6/7/2015 3:34:49 PM           True automatic                  True
esx2.example.com 192.168.10.1 UTC      6/7/2015 3:34:51 PM           True automatic                  True
esx3.example.com 192.168.10.1 UTC      6/7/2015 3:34:52 PM           True automatic                  True
esx4.example.com 192.168.10.1 UTC      6/7/2015 3:34:54 PM           True automatic                  True

Snapshots are a great feature, probably one of the coolest in virtualization. They can become a problem if they are not used appropriately, unfortunately sometimes we let them grow to an unmanageable size, which can bring performance issues and give us headaches when we need to delete them.

In this post, I will show you how to find out what snapshots are present in your environment, along with some other useful information, like size.

To run the commands below you will need to install PowerCLI (on windows), which is a way to manage a VMware environment programmatically using PowerShell scripting.

To get PowerCLI, go to: www.vmware.com/go/powercli

1) Once you have PowerCLI, open it up, a command prompt will appear:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Connect-VIServer -Server vcenter.example.com -User john

Name                           Port  User
----                           ----  ----
vcenter.example.com             443   john

// At this point you have a session open with your vCenter

2) Query your vCenter to find out what snapshots are present:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VM | Get-Snapshot | Format-list vm,name,sizeGB,create,powerstate

VM         : vm1
Name       : Before_upgrade
SizeGB     : 16.38431124389171600341796875
PowerState : PoweredOn

VM         : vm2
Name       : Before_package_install
SizeGB     : 12.368686250410974025726318359
PowerState : PoweredOn

Let me explain what is going on:
‘Get-VM‘ asks for the VMs that are running on your vCenter, PowerCLI returns an object for each VM and you then asks for the snapshots of each returned VM object by using ‘Get-Snapshot‘, then you take that output and format it by using ‘Format-list‘, but you are only asking for the information about ‘vm,name,sizeGB,create,powerstate‘

You can request any of the following:
Description
Created
Quiesced
PowerState
VM
VMId
Parent
ParentSnapshotId
ParentSnapshot
Children
SizeMB
SizeGB
IsCurrent
IsReplaySupported
ExtensionData
Id
Name
Uid

3) The above will give you the info you want, but I prefer CSV reports that I can share with the team or management. To get a good CSV report run the following:

PowerCLI C:\Program Files\VMware\Infrastructure\vSphere PowerCLI> Get-VM | Get-Snapshot | Select-Object vm,name,sizeGB,create,powerstate | Export-Csv C:\vm_snapshots.csv

I recommend taking a look at VMware’s best practices around snapshots:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1025279