Re: Modem not answering....

Jason Hess ( )
Thu, 12 Jun 1997 08:33:26 -0400

Marvin Anglin wrote:
> We have the same problem. If our user dials our number using a regular telephone and then redials with the computer, it works. Go figure? Anyone know whats happening??
> Marvin Anglin
> Atlanta On-Line InterNet
> 770-955-3000
> -----Original Message-----
> Sent: Wednesday, June 11, 1997 6:47 PM
> To:
> Subject: Modem not answering....
> List Members:
> I have recently discovered a sporadic problem that I am in the process of
> troubleshooting. That is why I am soliciting all of your expertise.
> I have some users that are reporting that sometimes my modems just ring and
> they never pick up. I have not been able to isoloate to a particular modem
> yet. But I was able to duplicate it one night. But then I call right back
> and it picks up.
> I am wondering if there could be a problem with one of the modems or
> perhaps there is a problem with the phone line. They are suppose to be on
> a circular hunt. When a modem dials another, does it send a special signal
> that tells the receiving modem to pick up?
> I am using all Supra 288 FaxModems with a Rocketport Multi-Serial port
> running on NT4.0 I am using RAS on these lines where the trouble is being
> reported. Any ideas as to what may be going on?
> All feedback is appreciated.
> Norris Sydnor
> Capital City Internet
> 1-888-5-CAPCITY
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> NTISP Mailing List
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> Part 1.2 Type: application/ms-tnef
> Encoding: base64

We are a rather large ISP here in Indiana (serving almost 5000
customers statewide), and we have seen some of these same problems (and
of course some even weirder:) ). To really diagnose this problem, you
need to find out what kind of "hunt group" is implemented on your phone
lines. I believe there are only two kinds: round robin and regular hunt
(I am sure there is another term for this). We use regular hunt groups
for ease of diagnosing bad lines, modems, etc, however round robins are
much more beneficial for the customer. In a round robin, if I call in
one time and get modem 7, if I dial right back, I should get the next
free modem going upwards (so 8 if nobody is on it). In a regular hunt, I
will get the FIRST available modem (so if nobody is on 1, I would get
that). The problem obviously occurs when say the first modem goes bad.
People will continue to get the first modem...a BIG problem. The only
time somebody can bypass the first modem is when another person is tying
up the phone line to the bad modem (not a very good percentage).
Anyway, once you have figured out which hunt group style you are in, it
is a little easier to determine where the problem is. If you are
in a round robin and you dial in and get a bad line, dial in again and
get a good one, suspect the modem behind the one you dialed in to. Even
better, make a list of what modems are being used and keep dialing.
Within 8 calls or show you should be able to pinpoint the problem fairly
easily. We also use line usage statistics to help us with bad modems.
Even if no signs of a bad modem are present, if we so a low usage on a
particular modem (especially one not at the far end of a hunt group), we
get suspicious.
Well, I hoped this wasn't "duh" knowledge and helped somebody out.
Good luck,

Jason Hess
Assistant Systems Administrator
CIOE Corporation