Tuesday, March 25, 2014

New Private Search Engine

I came across a new seach engine called Disconnect. It's a plugin that allows you to use several search engines without giving them your personal information.

ESXi 5.0, LUNS, SANs and Mulitsessions

We recently installed and configured new Overland S5000 SANs for our virtual environment. In doing so we noticed tons of errors once we added the SAN IPs to our iSCSI Software Adapter. The vmkernel.log was saying that the SANs were offline and then online and then offline and then online constantly.

The issue turned out to be that our new SAN doesn't support Multisessions. It doesn't like seeing the same subnet connecting to the SAN network cards and controllers.

What we ended up doing was putting each NIC on the two controllers in their own VLAN:

Controller 0, NIC 0 - VLAN 2
Controller 0, NIC 1 - VLAN 3
Controller 1, NIC 0 - VLAN 4
Controller 2, NIC 1 - VLAN 5

With this setup you will need 4 NICS on each host, one for each VLAN to ensure redundancy and multipathing. Each ESXi NIC would go to one VLAN.




Sunday, March 16, 2014

Intstalling Python easy_install

I'm posting this is case anyone gets confusing search results like I did. If you want to install easy_install type this at a command prompt:

sudo apt-get install python-setuptools

If for some reason you get an error you may need to do:

sudo apt-get update
sudo apt-get upgrade

Once it's installed you can use easy_install like this:

sudo easy_install web.py

or whatever program you need to install.


Removing LUNS and Datastores on ESXi Hosts 5.0 and above

We had a need to remove the LUNS from one of our SANS. If you go to your iSCSI Software Adapter and remove the SAN IP's from the properties (Dynamic and Static tabs), you will have issues when the ESXi host rescans the HBA's and VMFS stores. The reason is because you didn't remove the datastores from the host. The proper order to do this is:


  1. Unmount the datastore from each host
  2. Detach the LUNS from each host
  3. Remove the iSCSI IP's of the SAN from your iSCSI Software Adapter (or appropriate adapter)

Unmount The Datastore From Each Host
To do this you will need to go to the Datastore view and find the datastores attached to the LUNS. Right click and select unmount. A screen will come up letting you know if you can unmount the datastore. You should remove all VM's and it can't be part of a datastore cluster.

When you unmount the datastores it will ask you which hosts to remove them from. This saves time from having to go to each host and unmount.


Detach The LUNS From Each Host
To do this you will need to go to your configuration tab and then select Storage adapters. Select your storage adapter (mine is the iSCSI software adapter).

When you select your storage adapter you will see all of the LUNS on the bottom. Find the LUNS that you want to remove and right click and then select detach. Make sure you are selecting the right ones.

I had to to this for each host and each LUN. It took me a few minutes. I don't see an option to do this for all the hosts at the same time like we did with the unmounting of the datastore.


Remove The iSCSI IP's of the SAN From Your iSCSI Software Adapter (Or Appropriate Adapter)
Still inside your Configuration tab and Storage Adapter, right click your iSCSI Software Adapter and select properties. Go to Static entried and remove the IP's one at a time of your SAN. Do the exact same for the Dynamic tab. Once you do that click CLOSE and have it rescan.

The reason you want to go through all of this is because the datastores that are still mounted on those LUNS will cause issues if you just remove the IP's from the storage adapter. When it rescans it will take forever and could cause it to lose connection to the vCenter. Since the datastores were not unmounted the ESXi host doesnt know what to do and keeps trying to access it.

If you don't have any datastores on those LUNS, then you should be able to remove the IP's from the storage adapter and rescan.

User unable to login to RDP Farm after you re-enable them?

We had a strange issue. We had a user leave and since we knew when she was leaving i set the account to expire at a certain date. A couple d...