[aus.comms] uucp status & dial retries

david@csource.oz.au (david nugent) (12/30/90)

I'm using a HDB flavour uucp under Interactive Unix Sys V R3.2.

Does anyone know of a way I can change the "time between retries" that
uucico uses?  It seems to use some algorithm which increases the time
on each retry, but for various reasons I need to tune this a little,
since my host can get a little busy at times. A fixed retry rate would
work somewhat better than what's occuring now.  The result is a very
"lumpy" news and mail flow, which incurs some unnecessary overhead when
a large inflow hits.

Right now, I have a cron event set to delete /usr/spool/uucp/.Status/<site>
right before the poll event, but this seems somewhat kludgy.

What is the algorithm used anyway?

If this CAN be changed, are there any other "interesting" things I can
do to tune uucico?


Also, if anyone has any experience with running fas (I'm using 1.06) on
a dial/in dial/out line, I'd be interested in hearing from you. This
system has a "quirk" in that uucp sessions occur to a remote system
via a direct line to an MS-DOS system (it's COM2) with the trailblazer
on it's COM1 - the MS-DOS system acts as a serial bridge.  

The result is that carrier is never present on the line running to the
Unix system, and fas seems to indicate a "line lost - error 0" and
uucico aborts just after it succeeds at logging in (I suspect at the
point the dial script ends).  I thought of fiddling with the serial
cable and bridge software to raise the appropriate signal (link DTR
or DCD for example), but since this bridge works fine as is with the
standard Interactive drivers, and not with fas, I'm not completely
sure that's the problem.

Funny thing is, uucico sessions using the modem connected directly work
just fine with either driver.  However, I do need to run fas, since I'll
be using other protocols (namely ZModem) on the Unix sytem in the near
future with the modem connected directly, and I need hardware flow
control which the standard drivers don't support.


Thanks in advance,

 david

david@bacchus.esa.oz.au (David Burren [Athos]) (12/31/90)

In <772@csource.oz.au> david@csource.oz.au (david nugent) writes:

>I'm using a HDB flavour uucp under Interactive Unix Sys V R3.2.

>Does anyone know of a way I can change the "time between retries" that
>uucico uses?  It seems to use some algorithm which increases the time
>on each retry, but for various reasons I need to tune this a little,
>since my host can get a little busy at times. A fixed retry rate would
>work somewhat better than what's occuring now.  The result is a very
>"lumpy" news and mail flow, which incurs some unnecessary overhead when
>a large inflow hits.

The time field in the Systems file has an optional "retry" subfield.

	daytime[;retry][/grade]

Retry specifies the number of mintes before retrying a failed attempt.
According to the SunOS 4.1 (which uses HDB) documentation:

	In the absence of the ;retry entry, an exponential backoff algorithm
	is used (starting with a default wait time that grows larger as the
	number of failed attempts increases).  The initial retry time is 5
	minutes, and the maximum retry time is 23 hours.  If ;time is
	specified, that will always be the retry time.  Otherwise, the backoff
	algorithm is used.


>If this CAN be changed, are there any other "interesting" things I can
>do to tune uucico?

Read the documentation and find out.  You can specify a maximum grade of
file to send, what UUCP protocol to use, etc.
_____________________________________________________________________________
David Burren [Athos]                          Email: david@bacchus.esa.oz.au
Software Development Engineer                 Phone: +61 3 819 4554
Expert Solutions Australia, Hawthorn, VIC