Sunday, December 22, 2013

Basic VMware Interview Questions

I suggest you all to know what it is, not necessarily how and why about a product for a entry level vmware interview. Addition to these questions (after you have found answers and want to know more) I suggest you to go to vmwarelearning.com and go through the basic vsphere and ESXi videos.

  1. what is virtualization?
  2. what is a esx or an esxi?
  3. what is a vcenter ?
  4. what is a vsphere client?
  5. what is a vsphere web client?
  6. what is ha?
  7. what is ft?
  8. what is the difference between ha and ft?
  9. what is vmotion?
  10. what is svmotion?
  11. what is hot add?
  12. what is hot plug?
  13. what is drs?
  14. what is dpm?
  15. what is EVC & its benefits?
  16. what is update manager?
  17. what is VDP?
  18. what is iscsi & scsi, whats the difference?
  19. what is raid 0/1/5/10?
  20. what is FC/FCOE?
  21. what is hba?
  22. what is a lun? 
  23. What is SR-IOV?
  24. What is NSX?
  25. what is vmware horizon view or desktop virtualization?
  26. what is vmware vcloud or cloud computing?
  27. what are the advantages of vdSwitch over standard vSwitch
  28. what is the first thing that you do when you have a host which shows up as disconnected in the vcenter server?
  29. how do you find the version of vcenter server or esxi host?
  30. how do you find the driver/firmware version of the nic/hba?
  31. how do you restart management services in esx/esxi ?
  32. how to enable/disable ha/drs/ft for a cluster?



If you come across any other then please let me know in the comment section below and I will be glad to add them here.

Sunday, December 15, 2013

Keep your e Device Alive and stop updating your apps

You might have wondered why does my PC or smartphone gets slow after a year or two even though its the same hardware and same OS. Re installation of the OS of the e device seems to be a temporary fix but after sometime you are still stuck with the same problem of the device or system being laggy. We should all remember that hardware is the resource and it is not actually meant for the Operating System (OS) like your android or windows OS to use it all but it is a platform on which the OS must sit be a the mediator to the applications which are installed in it and the underlying hardware resources. Most of the time the OS remains the same inspite of few updates but it is the applications which gets updated the most. If you are an android device owner then you know what I mean. Everyday a new device with more aggressive hardware comes out and the app developers want to move on and use all the resources that they can get so that they can give a better user experience. If it is a game app then more the resources > more the fun but unfortunately our hardware can't keep up with this new updated app which is designed for higher end devices (even thought it still can be installed and played but it will start to annoy you with its lagging and slow performance). It is like a Cadillac or a Range Rover running on a hyundai entry level car's engine. The vehicle will still move but its undrivable and unbearable. In other words you buy a hyundai entry level car and upgrade its body to cadillac or rangerover. So My suggestion is after a year of the purchase of your device which was released not more than an year ago you please stop updating your applications. So please dont overkill your device and stop updating apps after some time when you feel it has started lag and before you update any app make sure you check out the change log and what has it that has changed in this new version and do you really need it or can you live without it since it doesnt appeal to you.

Monday, December 9, 2013

SSO rolls back during the vcenter 5.5 installation or during an upgrade from 5.1

Issue: It is a fresh vcenter 5.5 install or an upgrade from vcenter 5.1.x, whether it is a simple install or individual component install the SSO server installation rollsback without any error.

Resolution 1: Go to
 \\VMware-VIMSetup-all-5.5.0-1312299\Single Sign-On\prerequisites
and make sure all the prerequisites are installed. This issue occurs due to the failure of the installer to install the VMware-python.msi

Resolution 2: Make sure your password doesnt contain ;"'^\ or a space in it.

If these doesnt work then you may try
https://communities.vmware.com/thread/458077

Tuesday, December 3, 2013

vmware update manager error "an internal error occured in the vsphere client. details: unable to connect to the remote server"

Issue: Unable to download and install the update manager plugin.

what worked:
uninstall the update manager,
rename the old update manager directory,
reinstall the update manager.

What didn't work:
http://IP address:9084/vci/downloads/vmware-umclient.exe is not accessible via the web browser.
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&externalId=1014639
replaced the fqdn in upper case with the ip address but no go.
nslookup from the vcenter server to the vcenter server works.
while trying to enable the plugin it still gives the error
"an internal error occured in the vsphere client. details: unable to connect to the remote server."
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1020291
8084 and 8443 is working.
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1003602
odbcad32.exe connections for the update manager are valid and tested ok.
the vcenter db was in the local vcenter VM but the update manager was in a different database.
created a new UMDB2 but no go.
pointed it back to the old original udpate manager but no go.
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1039089
the connection to the database is successful.
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1034605
but no go.
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1004680
uninstalled the update manager and deleted the existing update manager databases and started the reinstallation of the vmware update manager.