vRealize Orchestrator VC plugin version

I keep forgetting this to be a problem so might as well write it down for myself and anyone else stumbling upon this.

When using vRO, in my case 7.5 or 7.6, you might get a problem where you are unable to add a vCenter instance of a vCenter version 6.7. The error is not very informative:

It doesn’t really scream out what the error is. But as I had seen the error before I had a hunch when my colleague was configuring vRO in our vRealize Automation platform.

On the vRO VMTN forum there is a post that contains the latest release of the vRO VC plugin – https://communities.vmware.com/docs/DOC-32872

Simply download the zip attached. Unpack the vmoapp file. Login to the vRO control-center on https://<FQDNorIP>:8283/vco-controlcenter/ and select “Manage Plug-ins”. Here under “Install plug-in” click browse and select the vmoapp file and upload. Accept EULA and install. After about 2 minutes the vRO will have restarted and the plugin updated.

vCenter instances can now be added 🙂

Updated udp_client.py for testing UDP heartbeats

A while back i stumbled on a set of KB’s for testing UDP heartbeat connectivity between ESXi and vCenter. I wrote this article to describe how to do it.

Now today I had to do the same and went back to these KB’s to find the script. This was however on newer 6.5 U2 hosts and not old 5.5 hosts. And as KB1029919 describes it is only applicable to 4.0.x to 5.5.x versions of ESXi.

Why is this important? Because between ESXi 5.5.x and 6.5 U2 the included Python was updated from 2 to 3. Some of you may know that there are many breaking changes in Python 3 when compared to Python 2 and some of those were present in the original udp_client.py script.

So I took the time to fix the few issues that the script had and upload a version to GitHub here. In the Python folder there is a version of udp_client.py that is Python 3 compatible and I included the original script as udp_client-v2.py for reference.

The major changes were in line 25 that print is now a function and has to be used with parentheses and the “%” change to “,” as seen here:

print "\nSent %s UDP packets over port %s to %s" % (numtimes,port,host) 

python 3:
print("\nSent %s UDP packets over port %s to %s", (numtimes, port, host)) 

After syntax error was fixed I found that there was a change to how “socket.sendto” works and it now expects a bytearray instead of a string. Simple fix was to introduce a int variable “datasize” set to 100 and change the “data” variable from “100” to “bytearray(datasize)” as seen here:

data = "100" 

python 3:
datasize = 100       
data = bytearray(datasize) 

After this the scipt works on a 6.5 U2 host and I was able to UDP connectivity.

This also marks the first time I have my own public Github repsitory so – yay! 🙂

Simple network debugging – ESXi and VCSA

I ran into an old issue yesterday with ESXi 5.5 and vCenter disconnecting after 60 seconds. The issues is described in KB1029919 and is due to heartbeat UDP packets from ESXi not reaching vCenter on port 902 within 60 seconds or at all.

Now how to test this! Luckily the KB has a simple Python script that allows you to send UDP packets. Just edit the script and insert the IP of your vCenter server and run it. It will default send 10 packets of 100 bytes.

Now the KB mentions using Wireshark as an option on the vCenter side but when using VCSA that is not really an option. Luckily VCSA 6.5 comes with tcpdump installed! 5.5 and 6.0 don’t but worry not, VMware to the rescue. You can install tcpdump on 5.5 and 6.0 by following KB2084896. This gives you access to a client on ESXi to send UDP packets and a monitoring option on VCSA to see if the packets arrive.

All that needs to be done then is run the following:

#on the VCSA
tcpdump -i eth0 udp port 902 -vv | grep <srcIP>

#on ESXi
python udp_client.py

And then look at the results. You can lose the “| grep <srcIP>” if you want to see all packets but depending on your setup there may be many ESXi hosts sending heartbeat.