Maximum number of tags or maximum string length


#1

HiHo,
I was wondering if there is a maximum number of tags I can assign to an object, e.g. to a VM. I realize that it eventually become hard to maintain them through the UI anyways. But is there a limit if I assign tags programmatically?

Same goes to the maximum string length for a tag. Is there a maximum length?

To give you some background:
We want to track every change happening on a VM in a ticket system. Provisioning, VM changes, starts, stops, edits,… and eventually retirement all should go into a ticket system for tracking.

But we also want to keep the ticket numbers in MIQ. So the idea was to use tags to keep tracks of all tickets related to that VM.

If we do that we could either use on tag per ticket (hence the question about maximum number of tags) or we could use one long string and assign it to the VM (hence the question about the maximum string length).

Any thoughts on that?

Regards,
Christian


#2

There are max lengths as I hit this on things like Service Names, but another area to look at based on your use case would be to use custom attributes on the VM, these are maybe a little friendlier than tags for your use case, as they are key value pairs?


#3

Keeping track of every ticket for a specific VM in MIQ doesn’t seem like the best place IMO. Shouldn’t the ticketing system allow you to look up the CI by the VM name and see all tickets associated? Also, what happens when the VM is retired and is no longer available in MIQ? You would then have a bunch of orphaned tags, right?


#4

If the VM is retired, it’s still in MIQ and the tag would remain useful. Or as part of the retirement process, we could clean up the tags.


#5

Custom attributes is probably a good alternative. I’ll look into that. A reason we wanted to use tags is, that you can use them to filter and one ticket could have been used to track the deployment of multiple VMs. So I could use the “ticket tag” to search for all VMs which have been deployed by the same ticket request.

It would still be nice to know the maximum length and number of tags for other use cases.


#6

I agree that tags are great, especially when you want to extend into provisioning scopes or RBAC features, but this sounds like a reporting item, and reporting allows you to report on custom attributes, so tags are a bit of a sledge hammer approach to your use case.

Are the tag limits defined by the database schema?


#7

The type of tag name in the db schema is “text” and according to http://www.postgresql.org/docs/9.1/static/datatype-character.html you need not be concerned about it’s length.

I also don’t see any limit on the number of tags assigned to an object.