What are the Send Expect Options

[Tomas Hoger]

On 4/24/07, isplist at logicore.net <isplist at logicore.net> wrote:
> > Check / adjust following lines in your config, this may help.
> >
> > send = "GET / HTTP/1.0\r\n\r\n"
> > expect = "HTTP"
>
> I've been trying to find the answer to this but am not having any luck. Anyone
> know the proper send/expect combinations for the following services;
>
> POP
> POPS
> IMAP
> IMAPS
> SMTP

For POP, IMAP, SMTP, it should be easy, just connect to service via
telnet and extract first word of output (should be '+OK', '*', '220'
respectively).  In lvs.cf, I guess you can omit send and put proper
word to expect.

This approach may produce "client unexpectedly closed connection"-like
messages in application logs.  Remember seeing something similar in
Postfix log.  It's caused by the fact that nanny only support
send-expect transaction, while for some services (e.g. SMTP), other
types of transactions may be prefered (e.g. send nothing, expect '220
blah ESMTP', send 'QUIT' to close connection correctly).

For SSL services, you may choose to write testing script, which will
connect to service via openssl and extract proper strings.  External
script can be used to work-around problem mentioned in previous
paragraph.  But I guess this has been pointed-out by others in this
thread as I was writing this reply.

th.