On Wed, Dec 16, 2009 at 5:21 AM, <Valdis.Kletnieks@vt.edu> wrote:
On Wed, 16 Dec 2009 07:06:55 EST, Mike Lieman said:
What's the word for 'mail server' in Lower Sorbian, and does your algorithm properly detect it in a hostname? See the problem here?
When the hostname at that IP address is exactly one incremented character different than the preceding address, and one decremented character different than the following address, and that pattern holds across a /24, they're probably not mail servers. Nobody has 256 'frzzmabs-1'..'frzzzmabs-256' servers in the same /24 for *anything* user-facing.
You clearly haven't set up webmail farms to handle half a billion accounts before. ^_^; We name our (many thousands of) webmail front end boxes as webXYYZZ.mail.$site.yahoo.com, so for cluster 3, farm 57, you end up with a string of hosts all in a row like web35701.mail.mud.yahoo.com web35702.mail.mud.yahoo.com web35703.mail.mud.yahoo.com web35704.mail.mud.yahoo.com web35705.mail.mud.yahoo.com web35706.mail.mud.yahoo.com web35707.mail.mud.yahoo.com web35708.mail.mud.yahoo.com ...etc... Take a look at the reverse DNS for the entire 66.163.178.0/23 subnet; you'll find that when you're doing things at large scale, you can't really get away from having sequentially numbered reverse DNS entries all in a row, exactly as you seem to think "Nobody has". :/ Matt