[rancid] Opengear console servers and RANCID

[Toby Smith]

Hi all,

I've been working with doing some stuff with RANCID and the Opengear
range of console servers.

I've got basic device support for monitoring Opengear console servers
themselves from RANCID going, that was pretty straight forward.

However, I was also interested in providing capability for devices
connected to an Opengear via a serial console cable to be monitored via
RANCID. The Opengear exposes the management console of all the serially
connected devices via the network in a bunch of ways (different SSH
ports, different SSH usernames etc).

I've got RANCID support for Ciscos behind an Opengear going at the
moment, but I've had to add a new device type (which I've awkwardly
called cisco-via-opengear).

Ideally I wouldn't have had to do this, but I ran into some differences
between real network device ports and Opengear-exposed serial console
ports. Really it's just a different clogin script, but I had to also add
a different rancid script (c-via-ograncid) to get it to call my
c-via-oglogin.

The simple difficulties I had to work around were:

- Initial connections didn't present a prompt after login until a "\r"
was sent down.
- When connected via an Opengear network-to-serial port, typing "quit"
or "exit" didn't close the connection.

The trickiest thing though was that RANCID had the idea of one router
per IP. When using the Opengear as a console server, you have serveral
different devices available from the one IP, but accessed with different
usernames or ssh ports.

What I've done is use a % symbol as a delimiter in router.db and in
.cloginrc to specify multiple hosts behind an Opengear. E.g.

router.db:
192.168.0.250%ciscoASA:cisco-via-og:up
192.168.0.250%cisco17xx:cisco-via-og:up

.clogin.rc:
add password 192.168.0.250%cisco17xx opengearpassword ciscopassword
add user 192.168.0.250%cisco17xx root:port3
add password 192.168.0.250%ciscoasa opengearpassword ciscopassword
add user 192.168.0.250%ciscoasa root:port2

And then in my c-via-oglogin script, I strip the bit after the % from
the router name before connecting.

This all seems to be working nicely and I've got it monitoring a couple
of cisco devices in my test lab. As I've said though, I've have liked to
not have had to add a new device type for this (to avoid duplicating so
much of the functionality).

I've got patches for all this sitting in my home directory at the
moment, but I thought I'd ask around if anyone else has any experience
with RANCID via console servers or if there's any other interest for
this before I tidy what I've got.

Cheers,
--Toby