Subject Re: [IBO] Crash
Author Paul Schmidt

On 11 Apr 2001, at 18:57, lester@... wrote:

> > The problem isn't Citrix getting ghost processes, but I don't think
> > you realise how rare DB server crashes really are, some people go
> > their entire careers without seeing a production server crash.
> With IB5.6 running, connections that are dropped are not closed. After
> a time, the excess connections cause an overflow which crashes the
> server. Thos only way to clear the problem is to stop and start the
> server at regular intervals - related to the error rate.
> IB6 eliminates this problem, and we are NOW running 24/7.

Okay I stand corrected, IB5.6 tends to crash if too many dead
connections hang about, two fixes, upgrade to 6.0, or make sure you
schedule a reset often enough that the problem doesn't occur, this
depends on how many is too many, and how often a connection gets
dropped, if it takes 500 connection drops, and you get one per day,
then use cron to stop and start the server once a week, and do the
same thing with Citrix.

> > As for ISDN call your ISDN supplier, and ask them to help you
> > resolve the connection problems, they can run tests on the lines and
> > their equipment to make sure everything is working on their end.
> Fat chance - ISDN is inherently 'unstable'. As it is a dialed
> connection, rather than point to point copper, packets are lost. Where
> network repeaters are build to use ISDN they include an auto-reconect
> to cover the problem. IB5.6 can not cope with these dropouts.

ISDN isn't dialed, it's connected, same as DSL and Cable, it's pretty
much point to point to the CO and then from there, many phone
companies run everything that isn't already digital trhough an ADAC,
and along fibre anyway.

These days there are enough choices in the mid-speed spectrum, that
you don't have to put up with low-speed stability and high-speed
prices. There is ISDN, *DSL, Cable and Microwave, and soon Cellular
is going to add another choice with G3. There is enough competition
between them, that you shouldn't put up with crappy connections. The
more choices there are, the more likely the people who own the box at
the CO, will want to keep you connected to it.

> It has taken us 18 months to get ISDN and Frame Relay stable. IBO, IB6
> and local caching works fine. IB5.6 can not be made stable.

Okay, so there are problems with 5.6, I still maintain that database
servers should not crash, and that when they do, you need to find out
why it crashes, and how to fix it. Bugging the ISDN provider to
stabilise the connection (at least to some degree), and upgrading to
IB6 (if possible) are the best game plan.

Paul Schmidt,
Tricat Technologies
Email: paul@...