There are a number of features that I have been asked for in Vinum. This page summarizes them and their status.
When a drive dies, it would be nice for Vinum to automatically migrate affected subdisks to another drive and recover their contents where possible.
Status: Coding begun.
It would be nice to be able to take a ``snapshot'' of a volume, a logical copy of the volume which doesn't change. This could be used for backups, for example.
Status: Kirk McKusick has something similar in the pipeline for ufs. I'm waiting to see what happens there.
Some people have asked for SNMP support.
Status: I've noted the request. I don't plan to do anything soon.
Currently, only concatenated plexes can be expanded in size. Adding subdisks to a striped or RAID-5 plex changes the address mapping. It's possible to do this, but the logistics are horrendous, especially if you want to do it on-line, and it would take a long time to do.
Status: Nothing planned at the moment.
Currently Vinum supplies its own statistics counters, which are much more detailed than iostat values, but iostat doesn't know anything about Vinum. It needs to find out about it.
Status: Nothing planned at the moment.
It would be nice to be able to spread the data on a Vinum volume over multiple systems. This isn't too difficult, but it doesn't bring the advantages you might expect: it wouldn't be possible, for example, for different systems to access the closest plex to them, since there would be no way to ensure data consistency.
Status: Nothing planned at the moment.
If you have input on these features, or another feature you'd like to see implemented, please contact me.