On Thu, Apr 16, 2009 at 09:58:37AM +0530, Kurian Thayil ([email protected]) wrote:
> I tried the script. Good work. But, one problem though. If the mail > server is firewalled (Netfilter) and if its blocking the client (one > where bash script is run - 192.168.0.10), then `telnet 192.168.0.20 25` > will not give any reply but just tries to connect indefinitely. At that > moment the script will not give the error message. Can we do anything > about it? You could abort the telnet using its escape sequence instead of using smtp quit, i.e., #! /bin/bash case "$( (sleep 5; echo -e '\033q') | telnet 192.168.0.20 25 2>&- )" in *' 220 '*) echo Success ;; *) echo Failed ;; esac If you want to be friendly to the mail server you could do both: case "$( (sleep 5; echo quit; sleep 5; echo -e '\033q') | telnet 192.168.0.20 25 2>&- )" in That will look a bit nicer in the mail server logs and may avoid tripping some spam/attack detection tools. Also, you may need to adjust the delays: the time a mail server takes to respond to initial connection may vary a lot, depending on things like its load and whatnot. Quite a few even deliberately wait some 10 seconds just to trip spamming software known to be too impatient. -- Tapani Tarvainen -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
