Storing UFS snapshots externally?

[Daniel E. Lynn]

Greetings all,

First, let me apologize if this has been asked before. If it has then my 
search skills must be lacking because I couldn't seem to find it in the 
lists anywhere.

I'm wondering if it is feasible to store snapshots for UFS on a separate 
drive, and if so if there is an advisable way of doing it. The basic 
idea is that I'd like to be able to mitigate any write overhead of using 
a lot of snapshots by using a separate disk for them entirely. Here's 
the proposed setup:

FreeBSD (/) is on ad0
Homedirs and userdata (/data) is on gm0 (ad2+ad3 mirrored)

I've been successfully using snapshots for /data, and the overhead on 
this system doesn't seem too bad (yet) but if I have more than a dozen 
snapshots, I get the feeling it could get messy. It'd be great if I 
could store the snapshots for /data on / someplace. I just don't know if 
there are any "gotchyas" that might keep me from doing this. Obviously I 
could symlink the /data/.snap dir to someplace on /, but I'm a little 
weary it might not be that easy. Ideas?