[isapros] Re: OT:Network Porblems
- From: "Young, Gerald G" <Gerald.Young@xxxxxxxxxx>
- To: <isapros@xxxxxxxxxxxxx>
- Date: Thu, 20 Jul 2006 10:21:23 -0500
Greg,
He forced the router to 100/Half?? That's not a good thing to do unless
you hard code the switch port that is connected to the router the same
way. You can end up with a lot of collisions that way. Do have
statistics on how many collisions you're getting. CRC errors can be
caused by too many collisions occurring which result in a packet being
"lost".
Does the switch support 1Gb speeds? Does the router? What happens if
you hard code the ports connecting the router and switch to
1Gb/AutoNegotiate(Full)?
Another thing to look at is whether or not STP is enabled on the switch
port connecting to the router. If it is and you aren't performing any
trunking between the router and switch, you might want to enable
portfast on the switch port connected to the router while also enabling
bpduguard. Usually, though, you'd only want to enable the two on ports
that are connected to end devices.
In general, if you can hard code speed/duplex on servers and switch
ports to which they are connected to the same, you can often times avoid
network communication issues because not all NICs work well in
AutoDetect.
Cordially yours,
Jerry G. Young II
MCSE (4.0/W2K)
Atlanta EES Implementation Team Lead
ECNS Microsoft Engineering
Unisys
11493 Sunset Hills Rd.
Reston, VA 20190
Office: 703-579-2727
Cell: 703-625-1468
THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY
MATERIAL and is thus for use only by the intended recipient. If you
received this in error, please contact the sender and delete the e-mail
and its attachments from all computers.
-----Original Message-----
From: isapros-bounce@xxxxxxxxxxxxx [mailto:isapros-bounce@xxxxxxxxxxxxx]
On Behalf Of Greg Mulholland
Sent: Wednesday, July 19, 2006 11:48 PM
To: isapros@xxxxxxxxxxxxx
Subject: [isapros] Re: OT:Network Porblems
The error itself is not helpful. it says "input error" it helps me
allot..:)
----- Original Message -----
From: "Thomas W Shinder" <tshinder@xxxxxxxxxxx>
To: <isapros@xxxxxxxxxxxxx>
Sent: Thursday, July 20, 2006 1:04 PM
Subject: [isapros] Re: OT:Network Porblems
It's important to know exactly what the errors are before replacing
hardware. Really need to see what's happening on the wire too.
Thomas W Shinder, M.D.
Site: www.isaserver.org
Blog: http://blogs.isaserver.org/shinder/
Book: http://tinyurl.com/3xqb7
MVP -- ISA Firewalls
> -----Original Message-----
> From: isapros-bounce@xxxxxxxxxxxxx
> [mailto:isapros-bounce@xxxxxxxxxxxxx] On Behalf Of Greg Mulholland
> Sent: Wednesday, July 19, 2006 10:02 PM
> To: isapros@xxxxxxxxxxxxx
> Subject: [isapros] Re: OT:Network Porblems
>
> I dont actually know what the definition is. They havent been
> able to tell
> me what the exact error means, no source ip or nothing.
>
> They were getting CRC errors and frame errors in the log but
> they seemed to
> have cleared up this morning.
>
> ----- Original Message -----
> From: "Thomas W Shinder" <tshinder@xxxxxxxxxxx>
> To: <isapros@xxxxxxxxxxxxx>
> Sent: Thursday, July 20, 2006 12:55 PM
> Subject: [isapros] Re: OT:Network Porblems
>
>
> What is the definition of an "input error" in this scenario?
>
> Thomas W Shinder, M.D.
> Site: www.isaserver.org
> Blog: http://blogs.isaserver.org/shinder/
> Book: http://tinyurl.com/3xqb7
> MVP -- ISA Firewalls
>
>
>
> > -----Original Message-----
> > From: isapros-bounce@xxxxxxxxxxxxx
> > [mailto:isapros-bounce@xxxxxxxxxxxxx] On Behalf Of Greg Mulholland
> > Sent: Wednesday, July 19, 2006 4:54 PM
> > To: isapros@xxxxxxxxxxxxx
> > Subject: [isapros] OT:Network Porblems
> >
> > OK i need some eyes on this one and since jim asked an
> > exchange question ill
> > take a stab.
> >
> > Previously the client had a 2mb Internet link with ye olde
> > cisco router, two
> > vlans. Two weeks ago they upgraded to a 4mb link with a brand
> > spanker of a
> > new cisco router, same 2 vlans. The cabling system was all the same
> > basically i had to do was pull the cables out from the old
> > router and stick
> > them into the new router, reconfigure the dhcp scopes and any
> > static devies
> > on the networks and all is good. Well vlan1 has worked a
> > treat since, which
> > brings me to vlan2.
> >
> > The client reported "no internet access" a while ago after a
> > bit of trouble
> > shooting and a cut to the chase the guys who manage the
> > router (externally)
> > tell me they are seeing 3-6 million input errors on vlan2's
> > interface log.
> > Rebooting the single switch attached to vlan2 fixes the
> > problem as it resets
> > the int but the errors will start occuring shortly after and
> > eventually
> > flood the interface and it drops again.
> >
> > OK so they tell me that its something on the vlan2 network
> > thats causing it,
> > i on the phone with the router guy one by one shutdown each
> > device then
> > unplug each cable from the switch then turn everything back
> > on one by one,
> > hoping he will say "ahh there it is what did you just turn
> > on". Mind you i
> > thought it is a long shot that one pc could genearate that
> > much traffic.
> > Anyhow i borrowed another switch of the same model and
> > plugged that in for
> > two days, same problem, i tried a different make swicth, same
> > problem, we
> > replaced the cables between the rooms as they are separated
> > by some 40 mtrs,
> > all the small patach cables, cables on the router, had them
> > out the other
> > day to reconfigure the interface and replace the four port
> > module, still the
> > same!!!!!!! Last night we turned everything off bar the
> > switch with the link
> > cable to the router plugged in and the router itself and its
> > still the same.
> > we have ordered a brand new switch which every network gets
> > given with this
> > setup, all configured to their specs in the hope that maybe
> > one day someone
> > screwed with ours and didnt document it. If that doesnt fix
> > it im lost. Has
> > anyone got any more ideas.
> >
> > My guts feeling is somethig the router guy told me the other
> > day in that he
> > had to force the router to 100half because that what the
> > swicth was telling
> > him it had, yet the swicth was all autosensing. I keep
> > thinking that its a
> > speed mismatch which can cause the links to drop. They reckon
> > its not but i
> > have my doubts
> >
> > If anyone has got any ideas, stupid or otherwise im all ears.
> >
> > Thanks Heaps
> > Greg
> >
> > p.s the pcs have been scanned for viruses and spyware before
> > i got to this
> > stage.
> >
> >
> >
> >
>
>
>
>
>
Other related posts:
