Re: custom pinger for satellite links

Michael Smirnov wrote:
> Please decide if this idea is completable.
> We have 2 links - a cheap(one-way satellite used only thru parent proxy)
> and a costly one (terrestrial).
> Also, the satellite link works very fast, but sometimes:
> - has very slow download speed (~500 bytes/s)
> - transmits no data after squid connect, and
> even lowering "read_timeout" didn't help.
> I'd like to write for Squid an external "HTTP-pinger" like this
> http://www.acme.com/software/http_ping/
> to test periodically this parent by downloading a small file.
> Maybe, it can be used in peer selection,
> to make Squid use only after successfull "http_ping".
> Can I get a short description about how Squid
> communicates with pinger?

Already partially done in the rproxy patch using a internal HTTP "ping"
request... there it is primarily intended to be used for monitor the health
check of the backend servers, but can just as well be used for monitoring the
health of normal proxy cache peers.

  http://devel.squid-cache.org/rproxy/

What might be needed to be added to this is HTTP RTT calculations. The HTTP
probes done in rproxy is currently only indicating "good/bad" according to
set criterias, not "better/worse".

And if you find that read_timeout does not work proper then this should be
fixed..

Regards
Henrik
Received on Mon Sep 09 2002 - 12:04:14 MDT