Hi SCC users,
[EMAIL PROTECTED] (Richard Adams) writes:
>Ronnie Hale pointed out your disconnect problem, i would like to comment
>on the SCC problem, please note i said "the" SCC problem and not "your" SCC
>problem as it seems you are by NO means alone.
>Over a period of time, there has been many comments about SCC interfaces
>dissapiering and just sitting there doing only half the work, by that i
>mean only receiving data but refusing to transmit.
>I would be interested to know more about your problem as we at PI1GOE have
>a problem with one interface doing as per described above all the time.
>By that i mean also 2@3 times a day.
>Our Symptoms are,
>1) data is received on a 9k6(scc) interface (which never dies i might add)
>and is retransmitted on a 4k8 interface.
>2) Multiple sendmail sockets open (3@4 at a time to one host) on the 4k8
>interface.
>It does not need to be sendmail, its just an example, when multiple hosts
>are ftping to, or via PI1GOE the same problem arises, the same applies to
>HTTP connections etc.
>It would seem buffers get overloaded, or something to that effect, ie, the
>9k6 interface works twice as fast as the data can be retransimited on the
>4k8 interface causing buffer/memory problems. Having sat behind different
>"listen" screens for hours at a time by PI1GOE i get the impression the
>problem is caused by the 9k6 interface acking packets like billyo and not
>having any room to store them as the queue's get higher and higher on the
>4k8 interface, with the enevatable effect that the 4k8 interface just stops
>transmitting, when that happens, it sees every packet on the 4k8 interface
>but just refuses to transmit.
>There is no need to reboot to get over the problem a small script i have
>running via cron, checks the interface with pings every 15 minutes, no pings
>returned will cause ifconfig to restart the interface and all is well again.
>There are never any signs or messages anywhere which could give even the
>smallest hint of where to start looking for the problem.
>I have explaned this problem to this list at least TWICE in the past, it is
>NOT only me that has this problem, a look at the archives will produce quite
>a few callsigns who all say they have the same symptoms in one way or
>another.
>Joreg DK1BKE has never responded to any of the comments, hints or kinks,
>made about this problem, i have tryed many things different timings, MTU's,
>window sizes, buffsize in /etc/z8530drv.conf, parms settings, realy you name
>it i've tryed it, all to no avail, there is a problem with the SCC driver
>but as finding out what it is, is like banging your head against a wall.
>Arno, if you would like a copy of my script which checks the interface
>activity with pings let me know, i will send you a copy, be warned its
>system spesific, however i am sure you will be able to convert it to your
>needs.
>And you thought your mail was long!!!!!.
>If there are others with this problem please speak now.
Here at my HAM machine PE1RLZ I'm using a USCC card and it's functioning
without trouble for approx a year now. I must say that the machine is not
heavy loaded and does not have much connections.
But the IRQ story in other postings triggered me.. I'm using irqtune to tune
the interrupt priority and gave the interrupt of the USCC card the highest
priority as provision. IRQTune solved lost IRQ's with serial ports on
another machine.
My HAM machine is running on a 386DX40 maybee that a fast pentium with PCI
bus also loses sometimes an interrupt from the slow ISA bus.
Good luck and 73,
Gerhard.
--
Gerhard Ahuis JO32EO It's good to be independent
[EMAIL PROTECTED] 145,550 MHz Linux the Ultimate HAM OS
Unsolicited advertisements subject to $1000 consulting fee.
