Category Archives: VMware

How to list the naa-numbers of LUNs and VMware VMFSs on a Dell EMC Unity system

EMC Unity

In the Unity the naa numbers (wwn) are listed in the “block” section, but not in the VMware section. If you view the LUNs from the host perspective, the naa numbers are visible, but in the list of LUNs  would have been easier. You can list all details from LUNs and datastores on the CLI by using the uemcli commands:

uemcli -d -u Local\admin -p [password] /stor/prov/luns/lun show -detail > unity.txt
uemcli -d -u Local\admin -p [password] /stor/prov/vmware/vmfs show -detail >> unity.txt

Now simply open the unity.txt file and voila: there they are!

Cisco DCNM server unresponsive

Cisco MDS

You’re running a DCNM virtual appliance and when you’re trying to log on, it looks like the appliance’s webserver is no longer active.

Connect to the Linux prompt of the appliance and do the following:

Stop DCNM services:


Open the psql prompt:

/usr/local/cisco/dcm/db/bin/psql dcmdb

log on with root password (user root is assumed)

Type the command:


This will produce tons of output, but just let it run and eventually it all ends and you just need to start the DCNM services again.

When done, quit the psql prompt:

dcmdb=> \q

Start DCNM services:



Reclaim thin provisioned space in VMware datastore

We were using a portable storage array as temporary storage array to store data from an older array that had to be reconfigured. Capacity was quite an issue and everything would barely fit (with dedupe and compression doing its best on the Dell EMC XtremIO we were using for this), but we discovered that provisioned space wasn’t immediately reclaimed, so we got a bit into trouble when space wasn’t immediately reclaimed when data was deleted from a VMware version 5 datastore.

We were facing two options:

  • Datastore VMFS version 6: Unmap automatically every 12 hours (not 100% sure about this interval)
  • Datastore VMFS version 5: Unmap manually from the ESXi command line:

esxcli storage vmfs unmap -l XIO-05-VMFS-013

Read more »

How to enable SSH on a VMware 5.5 ESXi host using the vSphere client

virtual machine

Recently I needed to make some edits on vmdk files in order to get rid of a reference to the change tracking files, as mentioned in Gabrie’s post: Cannot open the disk and could not open change tracking file. An SSH connection to a VMware ESXi host was required. SHH was disabled and I needed to enable it temporarily.

How to enable SSH on an ESXi host using the vSphere client

In vSphere, select the host you want to enable SSH on.

Select the “Configuration” TAB, then “Security Profile”. In the upper right select “Properties.

A new window opens, now select SSH (you may need to scroll down a bit) and in the lower right select “Options”.

Again a new window opens and here you can either “Start” or “Stop” the SSH daemon.

enable SSH

Free EMC trial software / virtual appliances

virtual machine

A quick heads-up this time about building your own lab environment

Sometimes you just want to run a VNX, Avamar, PowerPath, Data Domain or Isilon as a virtual machine to see how things work, or to write work instructions. And EMC offers a lot of these virtual appliances for free!

Take a look at these: