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There was a question today on the VMTN community forum about traceroute and ESXi. The user was troubleshooting a networking issue and logging into Tech Support Mode (Busybox Console) of ESXi, had noticed this common networking utility was not available. Since the user was working in a production environment, a re-compilation of a custom Busybox applet was out of the question and most likely unsupported by VMware. The user had to explore other avenues of troubleshooting, or did they have to?
It may not be well known, but within the Busybox Console, a Python interpreter is installed and accessible with a limited set of modules. Armed with this fact, you can actually create your own "poor man's traceroute" which gave you functionality similar to that of the actual traceroute/tracert implementation. This "poor man's" version was dubbed by a blog article I had found online (sorry, no ghetto in this name) by Leonid Grinberg - Learning by doing: Writing your own traceroute in 8 easy steps. The author goes into extreme detail providing step by step instructions on his python implementation of traceroute. Leonid provides a fully functional script at the end of his blog post, but he does caveat the following statement at the end:
This is actually not quite how the real
tracerouteworks. Rather than checking the IP addresses of the hosts and stopping when the destination address matches, it stops when it receives a ICMP “port unreachable” message, which means that the host has been reached. For our purposes, though, this simple address heuristic is good enough.
This was definitely another alternative if one needed functionality similar to that of traceroute. I used the author's polished version of traceroute.py and scp'ed the script onto an ESXi host. It ran just as well as the real traceroute on the classic ESX Service Console.
Though this may not have solved the original network issue, it is important to know what utilities you have at your disposal, even if it is not the actual tool that you are familiar with. There is always more than one way to do something and it is always good to know a few.
VMware does limit the number of "common" UNIX/Linux utilities that are bundled within the Busybox applet and based on demand and feature requests, we may see future utilities added to Tech Support Mode. One example is the release of vSphere 4.1, we saw the addition of nc (netcat) and tcpdump which are invaluable troubleshooting utilities for a vSphere admin. If there are other utilities that you feel should be included in the default Busybox applet, be sure to submit your feedback to either your VMware rep or file a feature request.
Cloning and/or moving vMA is not supported by VMware, this has been the case since VIMA 1.0. If you take look at the "Known Issues" in the vMA release notes, you will see there is no still workaround. Users may find it useful to be able to clone vMA for backup purposes or to deploy another vMA without having to re-download or re-uploading .OVF from your local desktop/VMware's website.
If you ever tried to clone VIMA 1.0 and boot the system up, you will notice a warning message during the init process when vMA verifies the system's UUID. If it detects that it has been cloned, it will actually disable itself and makes the vMA components unusable until you reinitialize vMA using vimaclean. This is still the case with vMA 4.1, except the vMA components are no longer disabled when you perform a clone.
You will just see the warning message during the init process, but all functionality continues to work. Before the vMA specific components starts up, it makes a call to /opt/vmware/vma/bin/verifyuuid. It verifies the system UUID which you can extract using dmidecode, this is the same UUID found within the .vmx entry called uuid.bios. When you clone a VM, a new UUID will be generated which causes an issue when it tries to verify.
Prior to vMA 4.x, VIMA 1.0 stored all it's configurations within a set of XML files located in /etc/vmware/viconfig, these files held the config for both the vi-fastpass targets and vilogger config and policies. With the release of vMA 4.0, these configurations were migrated to a sqlite3 database which is stored in /var/opt/vmware/vMA/vMA.db. Within this database, it also stored as the old flat file configuration, the system UUID of vMA. This is what verifyuuid was checking against to see if it was cloned or moved, you can actually query the vMA DB to extract this information using a simple SQL query.
To resolve the warning message, you just need to update the new UUID in the vMA DB using an update statement.
Instead of manually typing all that out, I actually created a very simple script that queries for the current system UUID and then updates the vMA DB with the correct UUID. Here is a sample execution:
Download: updatevMAUUID.sh
I suspect that VMware may have allowed cloning of vMA, but just did not update their release notes? The only thing you have to do is manually fix the UUID if you do not want to see the warning message. If you would like to fix this for VIMA 1.0, you will need to do the same thing except you need to modify the UUID found in /etc/vmware/viconfig/viconfig.xml and restart vMA for the changes to effect.