On Wed, Feb 13, 2013 at 7:57 AM, Ed Greshko <Ed.Greshko(a)greshko.com> wrote:
One thing of interest to note but which may not affect what the OP is
If the port being tested is listed as "filtered" by nmap
[egreshko@meimei ~]$ nmap -Pn -p143 imap.gmail.com
Starting Nmap 6.01 ( http://nmap.org
) at 2013-02-13 21:53 CST
Nmap scan report for imap.gmail.com
Host is up.
Other addresses for imap.gmail.com
(not scanned): 126.96.36.199
rDNS record for 188.8.131.52: oa-in-f108.1e100.net
PORT STATE SERVICE
143/tcp filtered imap
2>/dev/null >/dev/tcp/imap.gmail.com/143 && echo "yes"
will hang for quite some time....
I don't think this is related to the port being filtered as other
sites with filtered ports return quickly (same is true of down hosts).
Perhaps it is some other rude firewall behavior that causes the