route /f and client connectivity to file shares

The symptoms are as follows:

Server 1 - 192.0.2.8 DC/GC/IM/RID/SM/DNM/PDC/ISTG
Server 2 - 192.0.2.11 Member Server / Exchange
Server 3 - 192.0.2.3 DC/GC

Over a routed network clients periodically loose file share connectivity but
only to Server 1. When clients are in the lost state, they can ping all
servers and have fileshare connectivity to Server 2 and Server 3. Outlook
connectivity also remains active to server 2.

I have two workarrounds at the moment (1) Reboot Server 1 or (2) run the
route /f command followed by adding the default route.

My current workarround (2) is in place using a scheduled batch file every 20
minutes.

My question: Based on this series of criteria, has anyone experienced this
before?
My suplementary question: If you have seen something like this, what fixes
have you identified that I may try?

Regards
Rob Orton (MCSE of some kind)

Hello Rob.
From the scenario you depicted it seems that the default gateway to all the
servers should be the same, so it sholud makes no sense to delete the routing
table (also because the remaining two servers are always reachable by ping).
In your place I would check the server 1 for faulty hardware or network
settings.

--
Fabrizio Volpe
MCSE 2003/2000/NT
MCT

Turn off the power-saver features of all the nics involved on all the
machines.

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com
-----------------------------------------------------
Understanding the ISA 2004 Access Rule Processing
http://www.isaserver.org/articles/IS...cessRules.html

Microsoft Internet Security & Acceleration Server: Guidance
http://www.microsoft.com/isaserver/t...dance/2004.asp
http://www.microsoft.com/isaserver/t...dance/2000.asp

Microsoft Internet Security & Acceleration Server: Partners
http://www.microsoft.com/isaserver/partners/default.asp

Deployment Guidelines for ISA Server 2004 Enterprise Edition
http://www.microsoft.com/technet/pro...isaserver.mspx
-----------------------------------------------------



"BobbyO" <(E-Mail Removed)> wrote in message
news:FEBAFF86-5F95-4012-A643-(E-Mail Removed)...
> The symptoms are as follows:
>
> Server 1 - 192.0.2.8 DC/GC/IM/RID/SM/DNM/PDC/ISTG
> Server 2 - 192.0.2.11 Member Server / Exchange
> Server 3 - 192.0.2.3 DC/GC
>
> Over a routed network clients periodically loose file share connectivity
but
> only to Server 1. When clients are in the lost state, they can ping all
> servers and have fileshare connectivity to Server 2 and Server 3. Outlook
> connectivity also remains active to server 2.
>
> I have two workarrounds at the moment (1) Reboot Server 1 or (2) run the
> route /f command followed by adding the default route.
>
> My current workarround (2) is in place using a scheduled batch file every
20
> minutes.
>
> My question: Based on this series of criteria, has anyone experienced
this
> before?
> My suplementary question: If you have seen something like this, what fixes
> have you identified that I may try?
>
> Regards
> Rob Orton (MCSE of some kind)

I have noticed that the route table has direct route entries to the
workstations that are being affected by this connectivity issue:

For example:

Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 192.0.2.254 192.0.2.8
10
192.0.2.0 255.255.255.0 192.0.2.8 192.0.2.8
10
192.0.2.8 255.255.255.255 127.0.0.1 127.0.0.1 10
192.0.2.255 255.255.255.255 192.0.2.8 192.0.2.8 10
192.168.16.200 255.255.255.255 192.0.2.254 192.0.2.8 1
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1
1
224.0.0.0 240.0.0.0 192.0.2.8 192.0.2.8
10
255.255.255.255 255.255.255.255 192.0.2.8 192.0.2.8 1
Default Gateway: 192.0.2.254

Note the 192.168.16.200 route?

This is not a persistent route that has been manually added. It is an
address that has appeared automatically. I notice that over time more
directed host [is that the term] routes are collected by the windows server.

BTW: thanks for the response. This situation is driving me nuts.
"FabrizioV" wrote:

> Hello Rob.
> From the scenario you depicted it seems that the default gateway to all the
> servers should be the same, so it sholud makes no sense to delete the routing
> table (also because the remaining two servers are always reachable by ping).
> In your place I would check the server 1 for faulty hardware or network
> settings.
>
> --
> Fabrizio Volpe
> MCSE 2003/2000/NT
> MCT

The usual cause of specific host routes appearing is that the route that
the client machine has used is incorrect or non-optimal. When a router
detects there is a better route, it redirects the traffic. It also sends a
ICMP redirect message back to the client to inform it of the better route.
This info is used to set up a host route to the target machine using the
"better" gateway address.

BobbyO wrote:
> I have noticed that the route table has direct route entries to the
> workstations that are being affected by this connectivity issue:
>
> For example:
>
> Network Destination Netmask Gateway Interface
> Metric
> 0.0.0.0 0.0.0.0 192.0.2.254
> 192.0.2.8 10
> 192.0.2.0 255.255.255.0 192.0.2.8
> 192.0.2.8 10
> 192.0.2.8 255.255.255.255 127.0.0.1 127.0.0.1
> 10 192.0.2.255 255.255.255.255 192.0.2.8
> 192.0.2.8 10 192.168.16.200 255.255.255.255
> 192.0.2.254 192.0.2.8 1 127.0.0.0 255.0.0.0
> 127.0.0.1 127.0.0.1 1
> 224.0.0.0 240.0.0.0 192.0.2.8
> 192.0.2.8 10
> 255.255.255.255 255.255.255.255 192.0.2.8 192.0.2.8
> 1 Default Gateway: 192.0.2.254
>
> Note the 192.168.16.200 route?
>
> This is not a persistent route that has been manually added. It is an
> address that has appeared automatically. I notice that over time more
> directed host [is that the term] routes are collected by the windows
> server.
>
> BTW: thanks for the response. This situation is driving me nuts.
> "FabrizioV" wrote:
>
>> Hello Rob.
>> From the scenario you depicted it seems that the default gateway to
>> all the servers should be the same, so it sholud makes no sense to
>> delete the routing table (also because the remaining two servers are
>> always reachable by ping). In your place I would check the server 1
>> for faulty hardware or network settings.
>>
>> --
>> Fabrizio Volpe
>> MCSE 2003/2000/NT
>> MCT

This one was related to MTU. This issue is detailed in article 898060

I hacked the MTU size on the servers exhibiting problems and the
connectivity issue went away. This is kind of weird, because the servers are
all uptodate with latest patches and should not be exhibiting these problems.

"BobbyO" wrote:

> The symptoms are as follows:
>
> Server 1 - 192.0.2.8 DC/GC/IM/RID/SM/DNM/PDC/ISTG
> Server 2 - 192.0.2.11 Member Server / Exchange
> Server 3 - 192.0.2.3 DC/GC
>
> Over a routed network clients periodically loose file share connectivity but
> only to Server 1. When clients are in the lost state, they can ping all
> servers and have fileshare connectivity to Server 2 and Server 3. Outlook
> connectivity also remains active to server 2.
>
> I have two workarrounds at the moment (1) Reboot Server 1 or (2) run the
> route /f command followed by adding the default route.
>
> My current workarround (2) is in place using a scheduled batch file every 20
> minutes.
>
> My question: Based on this series of criteria, has anyone experienced this
> before?
> My suplementary question: If you have seen something like this, what fixes
> have you identified that I may try?
>
> Regards
> Rob Orton (MCSE of some kind)