ESX Update Failure because of lack of space in /core

On ESX 6.5, ran into an issue where updates from vSphere Update Manager (VUM) where refusing to install, due to 2 different errors, both having the same root cause.

VUM will through an error 15 in the UI, but if you look at the /var/log.esxupdate.log on the esx host itself, you will see in more detail what is going on.

It should be noted that “The host returns esxupdate error code:15” is a highly generic error message you might get at remediation, and can be caused by a bunch of different causes, including a corrupt update manifest file, corrupt bootbank, currupt VIB file or corrupt local  temporary patch database.

In the screenshot below of esxupdate.log, you can see that the temporary patch database was unable to be created in /locker/package/var/db/locker

different way this problem may present, is as a ‘broken pipe’ error ( ‘{errno 32] Broken pipe’

Notice that in both cases, it is failing on the large, 200mb VMware_locker_tools-light bundle


Both /core and /locker symbolic link to one of the ESX partitions. In this case, the partitions are on a mirrored SDCard. These are of type vfat

If you cd into /core you will end up in these partitions

Using DF -h you can check how much free space there is. As you can see in our case, just a little over 200mb remains.

That is not much, especially of you consider that the vmwaretools locker light bundle is itself about 200mb

Check the /var and /packages directory tree in this partition for files that can be cleaned up.

In the screenshot above, you can see that there appears to be a 73mb hostd core dump file sitting in /store/var/core

Unless you really need these to send to GSS (global support) for example, they can be deleted.

Similarly, you can also delete the old VMware tools bundles, unless you need them


These bundles are only used if you choose to auto-install VMware tools directly to a VM, using the UI or API

In practice, with most environments, this feature is not used (or very rarely), because most people either use the Open VMware tools included in Linux OS, or include VMware tools in a template or golden image. Or auto-install it with config management like puppet, Ansible or vRO.
So to save some space in case you have large update packages that don’t fit in /core, you can consider deleting these files too, they are about 200mb in all, after all.

Be aware though, that updates to esx-base or specifically named vmware tools updates, will of course, reinstall these files.


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