Leveraging VMware LogInsight for VM hardware inventory

There is no doubt that VMware LogInsight is a must for any properly managed vSphere environment. I'm explaining LogInsight benefits to all my customers. The main use case for LogInsight is troubleshooting but there are infinite number of other use cases where LogInsight can help.

During last LogInsight presentation to one of my customers I have got an interesting question if LogInsight can be used for change management. Change management is very broad term but all VM hardware changes should be in log files therefore there is potential to prepare specific interactive analytics to track VM hardware changes.

You can very simply find reconfiguration tasks for particular VMs logged by vCenter or ESXi hosts.

In ESXi logs reconfiguration log entries looks like

 2016-10-01T21:01:27.126Z esx01.home.uw.cz Hostd: info hostd[31C40B70] [Originator@6876 sub=Vmsvc.vm:/vmfs/volumes/d22648f3-b9848863/test_cmdb/test_cmdb.vmx opID=7c3fe7f0-976b-4afa-a182-6d9f074a6446-45173-ngc-25-78-fc98 user=vpxuser:UW.CZ\cdave] Send config update invoked  

And in vCenter tasks it looks like

 2016-10-01 21:01:27.434 vc01.home.uw.cz vcenter-server: Reconfigured test_cmdb on esx01.home.uw.cz in home  

The problem is that even we know there were some reconfigurations, there are no VM reconfiguration details like CPU, RAM, disks and NICs. This is the current state in vSphere 6.0 U2 and it would be great if logging of such details would be improved in future vSphere version but this is what it is at the moment.

However, lot of VM hardware details should be in vmware.log which is located in home directory of each VM. The problem is that these logs are placed on VMFS filesystem and not forwarded to syslog so LogInsight cannot be used for log analysis.

Fortunately, there is the blog of the best VMware virtualization blogger William Lam and more specifically his blog post "A Hidden vSphere 5.1 Gem – Forwarding Virtual Machine Logs (vmware.log) to Syslog Part 1". William very nicely explains how to redirect VM logs also to syslog.

You have to change following two advanced settings for each Virtual Machine you would like to redirect VM hardware logs to syslog server.

vmx.log.destination=syslog-and-disk 

vmx.log.syslogID=[YOUR-VM-NAME-OR-OTHER-ID]

And when VM hardware logs are available in LogInsight you can prepare custom analytics to visualize VM hardware changes over time and put it on to dashboard for future use. You can see my dashboard on screenshot below.

VMware LogInsight dashboard - VM Hardware Inventory 

I have exported my VM Hardware Inventory dashboard as LogInsight content pack and shared it here on github so you can download and import it in to your LogInsight and test it.

Content Pack source code from GitHub is embedded below ...
[ Download Content Pack from GitHub ]

And as always, any comments are more then welcome.

PRTG alerts phone call notifications

I have been asked by someone how to do phone call notification of critical alerts in PRTG monitoring system. Advantage of phone call notification against Email or SMS is that it can wake up sleeping administrator in night when he has support service and critical alert appears in central monitoring system.

My conceptual answer was ... use PRTG API to monitor alerts and make a phone call when critical alerts exist.

New generation of admins doesn't have problem with APIs but don't know how to dial voice call. That's because they are IP based generation and don't have experience with modems we played extensively back in 80's and 90's ;-)

At the end I promised them to prepare embedded system integrated with PRTG over API and dialing phone configured number in case of critical alerts.

Here is the picture of hardware prototype leveraging soekris computing platform running FreeBSD OS in RAM disk and making phone calls via RS-232 GSM modem.

Soekris computing platform and RS-232 GSM modem.

Here are relevant blog posts describing some technical details little bit deeper

• http://blog.igics.com/2013/12/freebsd-running-from-read-only-compact.html
• http://blog.igics.com/2014/01/gsmgprs-modem-siemens-es75-usefull-at.html

Working with VCSA embedded database

It's not often but sometimes you have to work with vCenter database. Usually it should be done only if you are instructed by VMware Support or there is VMware KB article (like this one http://kb.vmware.com/kb/1005680) solving your problem.

Please do it very carefully in production systems.

VMware vSphere admin veterans usually have experience with MS-SQL but what about vCenter Server Appliance (VCSA) with embedded database? It is not very different. VMware uses Postgresql database (aka vPostgres) so logically it is the same as in any other SQL database. I would say even easier than in MS-SQL but that's highly dependent on administrator background and previous experience. I'm probably biases due to my *nix history and open-source (GNU) general preference.

Here are basic logical steps how to work with vCenter database.

• Connect to database server
• Discover database tables
• Issue SQL commands
• Exit from database server

CONNECT TO DATABASE SERVER

Change working directory to vpostgres

cd /opt/vmware/vpostgres/current/bin/

Display database configuration

cat /etc/vmware-vpx/embedded_db.cfg

output should looks like

EMB_DB_INSTALL_DIR='/opt/vmware/vpostgres/9.0'
EMB_DB_TYPE='PostgreSQL'
EMB_DB_SERVER='127.0.0.1'
EMB_DB_PORT='5432'
EMB_DB_INSTANCE='VCDB'
EMB_DB_USER='vc'
EMB_DB_PASSWORD='WZL2^y<-k8boy br="" fa="">EMB_DB_STORAGE='/storage/db/vpostgres'

connect to database

./psql VCDB -U vc

Update 2015-09-15: For VCSA 6 use /opt/vmware/vpostgres/current/bin/psql 
-d VCDB -U postgres (password is not required)

and you are in.

DISCOVER DATABASE TABLES

It's really good to know what tables are in the database. You need table names to compose SQL commands allowing you to select, insert and update data in the database.

Postgresql have special DBA (database administrator) commands witch start with character \ (slash). You can list all DBA commands by sequence \?

The output looks like this

vc01:/opt/vmware/vpostgres/current/bin # ./psql VCDB -U vc
psql.bin (9.0.13)
Type "help" for help.

VCDB=> \?
  \d[S+]                 list tables, views, and sequences
  \d[S+]  NAME           describe table, view, sequence, or index
  \da[S]  [PATTERN]      list aggregates
  \db[+]  [PATTERN]      list tablespaces
  \dc[S]  [PATTERN]      list conversions
  \dC     [PATTERN]      list casts
  \dd[S]  [PATTERN]      show comments on objects
  \ddp    [PATTERN]      list default privileges
  \dD[S]  [PATTERN]      list domains
  \des[+] [PATTERN]      list foreign servers
  \deu[+] [PATTERN]      list user mappings
  \dew[+] [PATTERN]      list foreign-data wrappers

We want list database tables so the command we are looking for is

\dt

where output looks like

                    List of relations
 Schema |              Name              | Type  | Owner
--------+--------------------------------+-------+-------
 vpx    | vpx_access                     | table | vc
 vpx    | vpx_alarm                      | table | vc
 vpx    | vpx_alarm_action               | table | vc
 vpx    | vpx_alarm_disabled_actions     | table | vc
 vpx    | vpx_alarm_expr_comp            | table | vc
 vpx    | vpx_alarm_expression           | table | vc
 vpx    | vpx_alarm_repeat_action        | table | vc
 vpx    | vpx_alarm_runtime              | table | vc
 vpx    | vpx_alarm_state                | table | vc
 vpx    | vpx_binary_data                | table | vc
 vpx    | vpx_bulletin_operation         | table | vc
 vpx    | vpx_change_tag                 | table | vc
 vpx    | vpx_compliance_status          | table | vc
 vpx    | vpx_compute_res_failover_host  | table | vc
 vpx    | vpx_compute_res_user_hb_ds     | table | vc
 vpx    | vpx_compute_resource           | table | vc
 vpx    | vpx_compute_resource_das_vm    | table | vc
 vpx    | vpx_compute_resource_dpm_host  | table | vc
 vpx    | vpx_compute_resource_drs_vm    | table | vc
 vpx    | vpx_compute_resource_vsan_host | table | vc

ISSUE SQL COMMANDS

If we want select and view some data from database we use SQL statement SELECT. As an example  we will use first table from the list an it is vpx_access. Table vpx_access contains all vCenter users/groups who has access to vCenter and their roles. Here is SELECT statement:

select * from vpx_access

and output

 id  |          principal          | role_id | entity_id | flag
-----+-----------------------------+---------+-----------+------
   1 | root                        |      -1 |         1 |    1
 101 | VSPHERE.LOCAL\Administrator |      -1 |         1 |    1
 201 | VPOD01\vsphere-admins       |      -1 |         1 |    3
(3 rows)

Update and delete statements can be composed in similar manner following ANSI SQL Standard. Postgresql is ANSI-SQL:2008 standard.

EXIT FROM DATABASE SERVER

To exit from database server simply use DBA command \q

That's it pretty easy, isn't it? Working with vCenter database is not daily task of vSphere admin however we all know that sometimes you can be instructed by VMware support or KB to change something in the database. Don't be afraid - it's easy.

FreeBSD running from read-only compact flash disk and accessible over serial console (COM1)

I very often use FreeBSD for some automation tasks or as a network appliance. I like hardware like SOEKRIS, ALIX and other similar rotate-less and low power consumption hardware platforms. On such platforms I'm running FreeBSD on Compact Flash card and we all know about CF limited writes, don't we? So lets prepare FreeBSD system to run on top of read-only disk and prolong compact flash live.

After normal FreeBSD installation edit /etc/rc.conf and add following lines

tmpmfs="yes"
tmpsize="20m"
varmfs="yes"
varsize="32m"

This will instruct FreeBSD to use tmp and var in memory file system (aka ram disk) instead of normal disk mount points. This will in conjunction with read-only disk significantly save writes to flash disk however /tmp and /var mount points will stay writable which is important for lot of applications.

Now we can setup boot disk to be read-only. I can do it simply by editing /etc/fstab and change Options from rw to ro for boot disk. I can also change Dump from 1 to 0.
Parameter Dump (dump-freq) adjusts the archiving schedule for the partition (used by dump).
/etc/fstab should looks like example below:

# Device        Mountpoint      FStype  Options Dump    Pass#
/dev/ada0p2     /               ufs     ro      0       1

So now is my FreeBSD system ready to run on top of Compact Flash card in read-only mode so it eliminates flash write issue and system can run significantly longer then on read-write disk. Of course with read-only mode limitations but that's ok for lot of automation and network appliances. When I need some data disk I usually use another disk (or CF) just for data.

After FreeBSD reboot your mount points should look like on the screenshot below

root@example:~ # mount
/dev/ada0p2 on / (ufs, local, read-only)
devfs on /dev (devfs, local, multilabel)
/dev/md0 on /var (ufs, local)
/dev/md1 on /tmp (ufs, local)

Because I configure hardware appliance I would like to have possibility to control the system without monitor and keyboard. Unix systems were always ready for serial terminal consoles. So we can simply redirect console to RS-232 port and use it for system administration.

Here is the process how to do it. 

Add following command to /boot/loader.conf. You can do it simply by running following command 

echo 'console="comconsole"' >> /boot/loader.conf

which redirect all the boot messages to the serial console.

Edit /etc/ttys and change off to on and dialup to xterm for the ttyu0 entry. Otherwise, a password will not be required to connect via the serial console, resulting in a potential security hole.

The line in /etc/ttys should looks like below

ttyu0   "/usr/libexec/getty std.9600"   xterm   on secure

Update 2016-06-26: This is not needed any more for FreeBSD 9.3 and later because a new flag, "onifconsole" has been added to /etc/ttys. This allows the system to provide a login prompt via serial console if the device is an active kernel console, otherwise it is equivalent to off. 

Before editing the file I have to change read-only mode of my disk to read-write otherwise I will not be able to save the file. I can switch from read-only to read-write mode by command below:

mount -u /

If I want to change back to read-only mode here is how I do it

mount -a

This command remount all mounts with options in /etc/fstab so my disk is read-only again.

I leave the disk in read-write mode for now because I have to make the last configuration change, instruct the system to use COM port for console.

I run command

echo '-P'  >> /boot.config

to add -P option to /boot.config file. The advantage of this (-P) configuration is the flexibility. If the keyboard is not present then console message are written to

• serial and internal during boot phase
• serial during boot loader phase
• serial when system is running (in kernel phase)

If the keyboard is present in the system then monitor and keyboard is used as usual.
If the keyboard is absent the console is accessible over COM port.

Important note for systems without graphic card like SOEKRIS. Other virtual terminal entries in /etc/ttys should be commented otherwise you can see errors like

Dec 22 20:25:38 PRTG-watchdog getty[1469]: open /dev/ttyv0: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1470]: open /dev/ttyv1: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1471]: open /dev/ttyv2: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1472]: open /dev/ttyv3: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1473]: open /dev/ttyv4: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1474]: open /dev/ttyv5: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1475]: open /dev/ttyv6: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1476]: open /dev/ttyv7: No such file or directory
Dec 22 20:25:38 PRTG-watchdog getty[1477]: open /dev/ttyu0: Interrupted system call

I usually leave ttyv0 enabled otherwise you will not be able to use normal console (monitor + keyboard) on systems where VGA and keyboard exist.

So here is the screenshot from typical  /etc/ttys

#
ttyv0   "/usr/libexec/getty Pc"         xterm   on  secure
# Virtual terminals
#ttyv1  "/usr/libexec/getty Pc"         xterm   on  secure
#ttyv2  "/usr/libexec/getty Pc"         xterm   on  secure
#ttyv3  "/usr/libexec/getty Pc"         xterm   on  secure
#ttyv4  "/usr/libexec/getty Pc"         xterm   on  secure  
#ttyv5  "/usr/libexec/getty Pc"         xterm   on  secure
#ttyv6  "/usr/libexec/getty Pc"         xterm   on  secure    
#ttyv7  "/usr/libexec/getty Pc"         xterm   on  secure
#ttyv8  "/usr/local/bin/xdm -nodaemon"  xterm   off secure  
# Serial terminals
# The 'dialup' keyword identifies dialin lines to login, fingerd etc.
ttyu0   "/usr/libexec/getty std.9600"   xterm   on  secure

At the end don't forget to reboot the system to see if the changes took effect and everything work.

I'm writing this blog post primarily for me as a personal run-book but I believe it can be useful for some other FreeBSD hackers ;-)

Redirect DELL PowerEdge server serial port to iDRAC

Let's assume you use COM2 serial port for console access into your operating system. This is usually used on linux, freebsd or other *nix like systems. Administrator then can use serial terminal to work with OS. However it is useful only for local access. What if you want to access terminal console remotely? If you have DELL PowerEdge server with iDRAC 7 you can redirect serial communication to your iDRAC. You probably know you can ssh into iDRAC for remote server operations. When you are in the iDRAC you can use command "connect" which will connect you to your serial terminal.

To get it working a few steps have to be taken on Power Edge server.

1/ Configure iDRAC

• Go to Network & Serial
• Set IPMI’s Baud Rate for example 9.6 kbps (Serial Port Baud Rate)
• Apply Settings

2/ During boot enter the Server’s BIOS

• Go to “Serial Communication”
• Switch from “Off” to “On without Redirection”
• Switch Port Configuration from “Serial Device1=COM1;Serial Device2=COM2” to “Serial Device1=COM2;Serial Device2=COM1”
• Save Settings and Reboot Controller

After these steps the Server’s serial console is available via iDRAC:

Login to iDRAC using SSH and type “connect” at the prompt. After that the SSH session shows the serial console as if directly connected to the system’s serial port.

How to – use vmkping to verify Jumbo Frames

Here is nice blog post about Jumbo Frame configuration on vSphere and how to test it works as expected. This is BTW excellent test for Operational Verification (aka Test Plan).

PowerCLI One-Liners to make your VMware environment rock out!

Christopher Kusek wrote excellent blog post about PowerCLI useful scripts fit single line. He call it one-liners. These one-liners can significantly help you on daily vSphere administration. On top of that you can very easily learn PowerCLI constructs just from reading these one-liners.

http://www.pkguild.com/2013/06/powercli-one-liners-to-make-your-vmware-environment-rock-out/

Reduced vCenter DB by deleting old events and tasks from vCenter database

In vCenter MS-SQL Database is storage procedure called cleanup_events_tasks_proc which deletes old data based on event and task retention settings. vCenter retention settings can be setup in vCenter Settings though vSphere Client or changed directly in database. Using vSphere Client  is recommended.

Following example is copied from: http://communities.vmware.com/thread/191227?start=0&tstart=0

c:> "C:\Program Files\Microsoft SQL Server\90\Tools\Binn\OSQL.EXE" -S \SQLEXP_VIM -E
1> use VIM_VCDB
2> go
1> update vpx_parameter set value='' where name='event.maxAge'
2> update vpx_parameter set value='' where name='task.maxAge'
3> update vpx_parameter set value='true' where name='event.maxAgeEnabled'
4> update vpx_parameter set value='true' where name='task.maxAgeEnabled'
5> go
(1 row affected)
(1 row affected)
(1 row affected)
(1 row affected)
1> exec cleanup_events_tasks_proc
2> go
1> dbcc shrinkdatabase ('VIM_VCDB')
2> go
DbId   FileId      CurrentSize MinimumSize UsedPages   EstimatedPages
------ ----------- ----------- ----------- ----------- --------------
      5           1       81080         280       78776          78776
      5           2         128         128         128            128

(2 rows affected)
DBCC execution completed. If DBCC printed error messages, contact your system
administrator.
1> quit

DELL PowerConnect Time Configuration

Here is procedure how to setup it:

enable
configure
sntp unicast client enable
sntp server ntp.cesnet.cz
end

Here is how to verify:


console#show sntp configuration

Polling interval: 64 seconds
MD5 Authentication keys:
Authentication is not required for synchronization.
Trusted keys:
No trusted keys.
Unicast clients: Enable

Unicast servers:
Server          Key             Polling         Priority
---------       -----------     -----------     ----------
195.113.144.201 Disabled        Enabled         1
195.113.144.204 Disabled        Enabled         1

Here is how to check current time:


console#show clock

10:23:42 (UTC+0:00) Apr 29 2013
Time source is SNTP

Summary:

That's how to set time on DELL PowerConnect switches. Please note that time is in UTC +0:00 so when you want localize your time you can use "clock timezone" and "clock summer-time" command in conf mode but I don't like it. UTC time is better for troubleshooting.  

DELL OMSA LiveCD / LiveDVD

http://linux.dell.com/files/openmanage-contributions/om65-firmware-live/

Orion solarwinds

Orion Network Performance Monitor (NPM) makes it easy to quickly detect, diagnose, and resolve performance issues within your ever-changing corporate or data center network. It delivers real-time views and dashboards that enable you to visually track network performance at a glance. Plus, with our dynamic network topology maps and automated network discovery features, you can keep up with your evolving network without breaking a sweat. And Orion NPM is the easiest product of its kind to use and maintain, meaning you will spend more time actually managing networks, not supporting Orion NPM.

http://www.solarwinds.com/products/orion/

PowerGUI

PowerGUI is an extensible graphical administrative console for managing systems based on Windows PowerShell. These include Windows OS (XP, 2003, Vista), Exchange 2007, Operations Manager 2007 and other new systems from Microsoft. The tool allows to use the rich capabilities of Windows PowerShell in a familiar and intuitive GUI console.

Introduction to PowerGUI demo
http://www.powergui.org/shares/powergui/sbin/docs/PowerGUI_Overview/PowerGUI_Overview.html

PowerGUI Library » Virtualization
http://powergui.org/kbcategory.jspa?categoryID=290

PowerGUI and VMware vCenter Virtual Machine attributes
http://vcommunity.vizioncore.com/monitoring/vfoglight/b/weblog/archive/2011/02/07/easily-create-vfoglight-services-based-on-vcenter-custom-attributes.aspx

32 bit DSN on 64 bit Windows Server

c:\windows\SysWOW64\odbcad32.exe

Synchronize the Time Server for the Domain Controller with an External Source

Original article: Synchronize the Time Server for the Domain Controller with an External Source
Updated: March 28, 2003

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

By default, the primary domain controller (PDC) emulator gets its time from the BIOS clock. In a network with a single DC, that DC automatically has this role.

The PDC emulator establishes the time and date settings for all computers within its domain. If the time is not accurately set in the PDC emulator’s BIOS, all computers in the domain have incorrect time and date settings.

To prevent this, you can synchronize the domain controller with an external time source such as the time servers provided by the National Institute of Standards and Technology (NIST). For a list of the names and IP addresses of NIST time servers for your area, see the National Institute of Standards and Technology (NIST) Internet Time Servers link on the Web Resources page at http://www.microsoft.com/windows/reskits/webresources.

Note

* Be aware that the Network Time Protocol (NTP) is unauthenticated, and unencrypted, and it is possible for an intruder to spoof the time root source, causing the wrong time to be set on the DC. You can avoid this possibility by using IPSec to secure the transmission, by accessing the time root source by its IP address rather than its fully qualified domain name, or by purchasing an NTP-capable hardware clock for your DC time synchronization.

To synchronize the domain controller with an external time source

1. Click Start, and then click Command Prompt.

2. In the Command Prompt window, type the following line, where peers is a comma-separated list of IP addresses of the appropriate time sources, and press ENTER:

w32tm /config /manualpeerlist:peers /syncfromflags:MANUAL

The time sources you choose depend on your time zone. For example, if your domain controller is located in the Pacific Time zone, this line might read:

w32tm /config /manualpeerlist:131.107.1.10 /syncfromflags:MANUAL

In this example, the IP address of the timeserver is used instead of the fully qualified domain name for security purposes.

3. Press ENTER. You should get a message that the command completed successfully.

4. Type w32tm /config /update

5. Press ENTER. You should get a message that the command completed successfully.

W32time uses a variable poll interval based on the quality of timesync with the server. On DCs, this interval defaults to between 64 and 1024 seconds.

6. To immediately synchronize with the external time server, type w32tm /resync and press ENTER. You should get a message that the command completed successfully.

7. Type Exit and press ENTER.

=============================
BATCH FOR CZECH REPUBLIC
=============================
Here is quick batch for Czech NTP servers provided by CESNET.

 w32tm /config /manualpeerlist:"195.113.144.204 195.113.144.240" /syncfromflags:MANUAL  
 w32tm /config /update  
 w32tm /resync  

Virtual Machine - Disabling Time Synchronization 

If you are running your Active Directory domain controllers (more specifically PDC emulator) as a virtual machine in VMware vSphere another recommendation is to completely disable VM time synchronization with ESXi host. It is explained in VMware KB 1189 - Disabling Time Synchronization (1189). This will help you to mitigate the problem of Active Directory time issues after several VM operations (vMotion, snapshot, etc.) in case of ESXi host bad time. AD tolerance for time skew is 15 minutes max, at which point things start to fall over. For example during the vMotion operation, the PDC-E's time is adjusted to match the host's time (even though the "synchronize guest time with host" option is not checked on the PDC-E VM). This is a default behavior in ESX, and it should be changed as instructed in VMware KB 1189.

In a nutshell following VM configuration options has to be set to 0.

 tools.syncTime = "0"  
 time.synchronize.continue = "0"  
 time.synchronize.restore = "0"  
 time.synchronize.resume.disk = "0"  
 time.synchronize.shrink = "0"  
 time.synchronize.tools.startup = "0"  
 time.synchronize.tools.enable = "0"  
 time.synchronize.resume.host = "0"   

Note: The value of setting can be 0, false, FALSE, False. All these value have the same effect - not synchronize time after particular VM operation.

You can use following PowerCLI script to set these VM options to particular VMs.

 Clear-Host  
 $o = Add-PSSnapin VMware.VimAutomation.Core  
 $o = Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -Confirm:$false  
 
 # Connect to vCenter  
 Write-Host "Connecting to vCenter ..."  
 $VC = Read-Host "Enter one vCentre Server or multiple vCenter servers delimted by comma."  
 Write-Host "Enter vCenter credentials ..."  
 $CRED = Get-Credential  
 Connect-VIServer -Server $VC -Credential $CRED -ErrorAction Stop | Out-Null  
 
 # Array of virtual machine names   
 #$vm_names = "W2K8R2-test1","W2K8R2-test2"  
 $vm_names = "W2K8R2-test"  
 
 foreach ($vm_name in $vm_names) {  
  Write-Host "VM: [$vm_name]"  
  try {  
   $vm = get-vm -Name $vm_name -ErrorAction Stop  
   New-AdvancedSetting -Entity $vm -Name tools.syncTime -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.continue -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.restore -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.resume.disk -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.shrink -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.tools.startup -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.tools.enable -Value 0 -Confirm:$false -Force:$true  
   New-AdvancedSetting -Entity $vm -Name time.synchronize.resume.host -Value 0 -Confirm:$false -Force:$true  
  } catch {  
   Write-Warning -Message "VM doesn't exist";  
  }  
 }  
 Disconnect-VIserver -Server $VC -Force -Confirm:$false  

Current version of PowerCLI script is available on GitHub here.

VMware: Timekeeping best practices for Windows

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1318

Getting the network adapters’ order in Windows

http://saltwetbytes.wordpress.com/2009/10/17/getting-network-adapter-order-in-windows/

VMDK Handbook - Basics

http://sanbarrow.com/vmdk-basics.html

NIMSOFT - flexible monitoring solution

http://www.nimsoft.com/solutions/index.php

Nice syslog explenation

http://content.hccfl.edu/pollock/AUnix2/Logging.htm

Mepis Linux

LiveCD, System Recovery CD, Linux USB Boot Key
https://www.mepis.org/