As some of you may have noted, we now have a couple of new options to
choose when blocking users. Tim Starling, who implemented the feature,
posted the following clarification on the wikitech-l list:
Tim Starling wrote:
A couple of people asked me about interaction between
various kinds of
blocks and block options, and indeed, in some cases the behaviour was
undefined or accidental. I've now implemented the following rules:
* The "anon only" and "prevent account creation" options will be
silently
ignored on username blocks.
* The precedence of blocks in cases of conflict, from highest to lowest, is:
* Username block
* Single IP block
* Range block
* Autoblock
This holds regardless of the anon-only option. This means that anon-only
range blocks or IP blocks can be used to mitigate the effects of autoblocks
on shared IP addresses, because an anon-only block will allow logged in
users to edit regardless of the presence of a matching autoblock. This has a
potential to be counterintuitive -- unblocking someone's IP can in fact
cause them to be blocked. But I thought it was better than the other solutions.
Given the above, would it now be advisable to block the entire AOL proxy
pool from editing by unregistered users? This would have the side
effect that AOL users would no longer be hit by random autoblocks.
(If you're unfamiliar with the AOL proxies and why they're a problem for
us, please see [[Wikipedia:Advice to AOL users]] and [[Wikipedia:Dealing
with AOL vandals]], plus the associated talk pages.)
--
Ilmari Karonen