Back in CommentSpammerBehavior I wrote that checking the HTTP Referer header wasn't worthwhile because everyone got it right. That is nolonger true; a significant number of comment spam attempts come fromsome group that is using HTTP Referer headers of the (illegal) form'URL1, URL2, ..., MyURL' (where MyUrl is the URL of my 'write a comment'form); the number of URLs varies.

(A few times they have left out the spaces after the commas, making

Unfortunately, one of ZFS's current issues is that it does not have anydirect support for the sort of data migration you need to do for longterm storage management . There arethree possible approaches to this:

• direct migration support: not present.
• growing a pool with the new storage then shrinking it by removing theold storage: while ZFS can grow pools it can't shrink them.
• add the new storage as a mirror and then detach the old storage: youcan't mirror raidz or raidz2

One of the things I have become conscious of recently is that managingyour storage over the long term without lots of pain and withoutdisturbing your users requires an additional set of features that youmay not realize you need. (Partly I came to this realization by blithelyproposing a design for our next generation of storage without reallythinking about the issues, and then having people gently point out theproblems I had missed.)

(By 'painless' I mean that it does not take a lot of sysadmin effortto deal

It's simple: the advantage of a SAN is that it decouples your storage spacefrom your servers .

This means that you can deal with each side independently; you can addstorage or move storage without having to change the server hardware,and you can replace (and add) servers without having to do anything toyour disks. In turn this means that you can use common garden varietyservers instead of big monster servers that are designed to hold loadsof disks, which means it is much easier to maintain and