Comments on: Viewing CDP Data on VMware ESX

By: Vishal

Vishal — Tue, 23 Aug 2011 21:37:43 +0000

Scott,

Thanks for the article, I notice that the tlv_length is maxing out at 31 and device_id field is alaso maxing out to 31chars. Is there such limitation? I am noticing that the host name is gettign truncated to 31 chars. Is there a known issue?

Thanks
Vish
Looks for Real name and the truncated name in the following trace.

[root@ht-152123456789012345678901234567890 ~]# hostname
ht-152123456789012345678901234567890 <- Real name

By: Ian

Ian — Thu, 27 May 2010 14:20:10 +0000

Excellent. Thanks Scott. This helps when you have a new build and the ESXi system isn’t online yet due to a wiring goofup.

By: Christoph Wegener

Christoph Wegener — Thu, 05 Nov 2009 01:55:14 +0000

Yay. Number on result on Google for “vmware-vim-cmd cdp info” is this post and it’s exactly what I was looking for.
That little balloon showing the CDP info in the vSphere Client is just clumsy!

By: aenagy

aenagy — Mon, 25 May 2009 15:10:42 +0000

With CDP enabled on ESX/ESXi will the host simply recieve CDP packets or will it also generate CDP packets? Our network team will veto any device generating CDP packets that they do not administer.

Thanks.

By: Jennifer Geisler

Jennifer Geisler — Thu, 26 Mar 2009 04:15:33 +0000

Hi Scott. I’m glad that you found that viewing CDP data from the Cisco is easy! As the Manager of Network Systems Networking and Switching for Cisco, I’m always heartened to hear about people who can provide insight and knowledge about Cisco. You definitely have some sharp readers! I look forward to reading more of your blog. Best, Jennifer.

By: William

William — Wed, 25 Mar 2009 03:46:38 +0000

Whoops, my previous comment mentioned vimsh, but the command used is actually part of the standard Service Console utilities.

Though the same information can be extracted via vimsh using the following for ESX 3.5+

vmware-vim-cmd hostsvc/net/query_networkhint

on ESXi 3.5+

vim-cmd hostsvc/net/query_networkhint

–William Lam

By: William

William — Wed, 25 Mar 2009 02:31:18 +0000

Hi Scott,

Great post, vimsh is an awesome tool to pull out information that just is not available through the traditional methods. After reading your post, you motivated me to create a small Perl script that utilizes the VI Perl Toolkit to extract the CDP information provided with either vCenter or individual ESX/ESXi instance: http://engineering.ucsb.edu/~duonglt/vmware/cdp.pl

The Perl script functions similar to that of my VMware Health Script, you can take a look at the VMTN document for instructions, but it works similar to those of the VI Perl Toolkit Utilities

I’ve just updated with few fixes/enhancements:
http://communities.vmware.com/docs/DOC-9420

–William Lam

By: wharlie

wharlie — Wed, 25 Mar 2009 00:58:46 +0000

You can also use:
vmware-vim-cmd hostsvc/net/query_networkhint
as per http://kb.vmware.com/kb/1007069

By: DK

DK — Tue, 24 Mar 2009 23:27:51 +0000

awesome. i was looking for something like this, not for cdp but for vmnic info.