Underscores in hostnames

[phil]

I've been wondering about this for a while, but with manic_mark posting a video it actually presented a problem...

The video was at www.manic_mark.unicyclist.com. When I try this, the university proxy (squid) whinges about the underscore in the hostname. I had to download the video using wget on a Solaris server with a direct connection.

Should they have underscores in? After a quick look I can't find any mention of underscores in a relevant RFC, and I can't think of a reason as to why underscores are evil...

Phil

[leo]

Underscores are no valid characters in hostnames.
same for nummeric hostnames, so 444.unicyclist.com would be invalid, but that would work on all machines except old BeOS.
For that reason I (.nl registrar (http://www.sidn.nl/sidn/flat/Deelnemers/Overzicht/Deelnemers_Categorie_I/index.shtml#U)) cannot claim 128.nl, very tricky I managed to get www.128.nl.

The future is gonne be much more mess: http://cr.yp.to/djbdns/ipv6mess.html
I'm now playing arround with the protocol, but guess what happens if you try to access localhost with a(ny?) browser: http://::1

Leo Vandewoestijne
http://www.unixcycle.com/
http://www.ripe.net/perl/whois?UNICYCLE-MNT

[leo]

forgott
I can't find any mention of underscores in a relevant RFC

it somewhere described (in a RFC) as a-z 1-0 and -

[phil]

Originally posted by leo
Underscores are no valid characters in hostnames.
same for nummeric hostnames, so 444.unicyclist.com would be invalid, but that would work on all machines except old BeOS.
Ah, I see... that makes sense. Presumably while they're not allowed enforcing it is very lax... this is the first time I've noticed not being able to get to a host with an underscore in; it works every other way I can think of.

Thanks,

Phil

[leo]

yes, it's most of the times the client (or cheapo routers in between). Try these:

http://whatever_something.servermonitor.org/
should work, it does with me

http://3639261710/
suprise

but since many spammers used this to hide themselfs.
like http://www.sex.com%401360083040
microsoft disabled this in MSIE, however it still works using:
ping 3570197104
on the DOS-command prompt.

Oh ya, not to make you worrieng, about IPv6,
that latest satelite (got many secret pictures) of NASA,
is (since a "low" budget of $13,000,000.-) completely managed using FTP and SSH...
Hope the deamons come up after switching over.