Ship RHEL 6 or CentOS6 syslogs

Reference more for myself than for y'all, but you get the shared benefit.

To ship the logs from RHEL6 or Centos 6 to a remote syslog server, edit the following file: /etc/rsyslog.conf


At the bottom of the file, remove the comment from the remote-host entry, and update with your server name or IP. Example:
*.* @@192.168.40.15:514

Restart the rsyslog service:
service rsyslog restart

Make sure you are receiving the logs at your syslog server.

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Dustin Shaw
VCP

Install VMware Tools on RHEL 6 or CentOS 6

Below is the process to install VMware Tools on RHEL 6 or CentOS 6. This guide is more here for me than anyone else, but I hope that you can benefit from it.


Install the Pre-Requisites:
yum install make gcc kernel-devel kernel-headers glibc-headers perl


Start the VMware Tools installation process on your VM:





Mount the VMware Tools installation media:
mkdir /mnt/cd
mount /dev/cdrom /mnt/cd
Expected warning:
mount: block device /dev/sr0 is write-protected, mounting read-only


Extract the installer:
cp /mnt/cd/VMwareTools-9.0.10-1481436.tar.gz /tmp/
umount /mnt/cd
cd /tmp
tar xvf VMwareTools-9.0.10-1481436.tar.gz
cd vmware-tools-distrib/


Install tools (accepting all defaults):
sudo ./vmware-install.pl -d

Reboot the VM to verify that the service starts up automatically as expected.
shutdown -r now


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Dustin Shaw
VCP

Extend a volume in RedHat 6 or CentOS 6

To extend a partition on a VM on CentOS 6 or RHEL 6, do the following:

Extend the Partition in vSphere to the size that you need:

in the VM, refresh the Partition Tables by the following command:

echo 1 > /sys/block/sda/device/rescan
Run fdisk to create a new primary partition:

fdisk /dev/sda

Press p to print the number of partitions
Press n to create a new primary patition
Press p for primary
The partition number should automatically be selected, and press enter twice to accept the beginning and ending blocks on the free space.
Press w to write the changes.

Reboot the system: shutdown -r now

Verify that the new partition exists:
fdisk -l

Convert the new partition to a physical volume:
pvcreate /dev/sda3
Extend the Physical Volume (run vgdisplay to obtain the name of the Volume Group; default is VolGroup00):
vgextend VolGroup00 /dev/sda3

Extend the Logical Volume (run vgdisplay to obtain the free space and replace # below, and lvdisplay to obtain the name of the Logical Volume; default is /dev/VolGroup00/LogVol00)
lvextend -L+#G /dev/VolGroup00/LogVol00

Expand the ext3 online using the following command (substituting your proper Volume Group and Logical Volume names):
resize2fs /dev/VolGroup00/LogVol00

Confirm that your new space is available:
df -h



This was written using VMware's KB article on the subject as a reference.

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Dustin Shaw
VCP

vRanger 5 and ESXi Performance Settings

Everyone should know that the previous recommendations from Quest were to increase the CPU Reservations to 1500 on ESX servers for the best performance from vRanger.

I just recently ran across an article (here) from Sept 2011 detailing that this is NOT the case for ESXi. There is no performance gain on ESXi by increasing the CPU reservations from the default 293.

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Dustin Shaw
VCP

vRanger error "There is an error in XML document"

I ran into an issue with one of our repositories - every job in the particular repository was failing with the error:

An internal error occurred during execution, please contact Quest support if the error persists. Error Message: There is an error in XML document (823, 223).

This error is commonly caused by a corruption or issue with the manifest file as detailed here.

To fix it, go into the manifest file for the repository (GlobalManifest.metadata), make sure that all trailing brackets are closed, and add </vRangerGlobalManifestFile> at the end of the document.

Save and test.

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Dustin Shaw
VCP

vCenter Server 5 Service Fails

We had an issue with the vCenter Server 5 Service failing recently. Basically what happened was the VMware VirtualCenter Server service failed (out of the blue) with the following Informational Event ID 1000 logged in the Application log:

The description for Event ID 1000 from source VMware VirtualCenter Server cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

Starting VMware VirtualCenter 5.0.0 build-623373

the message resource is present but the message is not found in the string/message table

Followed by another Info Event 1000:

The description for Event ID 1000 from source VMware VirtualCenter Server cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

Log directory: C:\ProgramData\VMware\VMware VirtualCenter\Logs.

the message resource is present but the message is not found in the string/message table

And followed by an Error Event 1000 (upon it attempting to auto-restart the service):

The description for Event ID 1000 from source VMware VirtualCenter Server cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

Failed to intialize VMware VirtualCenter. Shutting down...

the message resource is present but the message is not found in the string/message table

First try was to restart all the vCenter services - only the VMware VirtualCenter Server service was offline; all other services (like VMware VirtualCenter Management Webservices) were still online. This obviously failed with the same error as before.

All of the SQL services were verified online (these are kept on a separate server due to the size), and accessible. I ran across a similar Discussion thread in VMware Communities, which pointed to issues inside of the SQL Database. Based off of this, I decided the first order was to look at my SQL server to see what was going on there. I was able to log in, and verified that everything was up. Then I looked at my logs, and saw Event ID 17053:

C:\VCDB.ldf: Operating system error 112(There is not enough space on the disk.) encountered.

 And instantly I knew my problem. Some yahoo (namely the yahoo writing this article) must not've been paying attention when installing the VCDB database, and stuck it in the root of the C drive. Naturally, that yahoo had to fix his own problem...

So I went into Microsoft SQL Server Management Studio, and ran the following command:

alter database VCDB modify file ( name = vcdb , filename = 'E:\SQL\MDF\VCDB.mdf' )
alter database VCDB modify file ( name = vcdb_log , filename = 'E:\SQL\LDF\VCDB.ldf')
go

Then I Offlined the database (Right click, Tasks, Take Offline), and moved the files to their new homes. Then I Onlined the database, and verified that the path was correct for it. You can see the full process of how to move a SQL database here.


Once this was done, I went back to my vCenter Server, and was able to bring all my services online without incident, and was able to again go in and manage my vCenter 5 Server via vSphere Client.

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Dustin Shaw
VCP

WNLB and VMware

So I believe I've found an (known) issue with 2003 Windows Network Load Balancing and VMware.
VMware reports that WNLB on Windows 2003 Servers does not behave as expected here. Basically the article says the the NLB will point to one of the servers, not all of them, when running in unicast. They give you two fixes: use multicast; or reconfigure your Port Groups (or vSwitches) to prevent RARP Packet Transmissions. Interesting thing, with the current environment these servers are hosted in, I am unable to either run multicast or disable Switch Notify. I'll have to take that up with the Network Team, or perhaps investigate some NLB hardware.

So here's where I'm left with - these servers are not supposed to go down (hence the NLB), but they are everyday at 4AM (fun call). This is when backups are running, so I'm adjusting the time to see if the issue follows.

What appears to be happening is that when snapshots are taken for backups, the NLB seems to freak out at the one dropped ping. Currently the backups all run at once, which makes them all hiccup at the same time, killing the NLB for a good reported 45 minutes (no idea why so long). If the issue follows the backups, perhaps staggering the backups might solve the problem (let the NLB roll from one server to another).

I'll keep you posted on what I find.
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Dustin Shaw
VCP