Too long disk alias and/or description used to be sent to vdsm without any check.
vdsm used to truncated them silently and caused a corruption in the volume's metadata.
Too long alias and/or description are truncated in the engine side so that the maximum length of the json disk description field sent to vdsm is now limited to 210 bytes.
The priority is given to the alias. That means that we read the alias first, and only if there's enough space, we take a part of/the entire description.
If the alias is too long, it will be truncated and the description will not be sent to vdsm at all.
There's no corruption in the volume's metadata.