Network connection lost on DHCP IP renew

[peter]

Hi,

I am running Windows XP Pro, SP2.
Our LAN has a SonicWall Pro firewall acting as the DHCP server, and my
IP lease expires and renews around 10:30am each day.

At the time that my IP renews, windows temporarily looses it's network
connections. If windows explorer is connected to a network share, I
get a message like:
\\server\share is not accessible. You might not have permission to use
this network resource. Contact the administrator of this server to
find out if you have access permissions.
The network location cannot be reached. For information about network
troubleshooting, see Windows Help.

Separately, Responsive Timelogger which accesses a DBF database on the
network crashes and disappears.
And a proprietary app connecting to a network SQL Server database
looses it's connection.

But I can immediately browse back to the network share and start the
two network database apps again.

I understood that DHCP renewals were supposed to be seamless, and not
cause disruption.

Short of forcing a renewal manually before opening any apps (ipconfig
/renew), is there a way to stop IP lease renewals effecting my network
connection?

Regards,
Peter

 

[Lanwench [MVP - Exchange]]

Hi,

I am running Windows XP Pro, SP2.
Our LAN has a SonicWall Pro firewall acting as the DHCP server, and my
IP lease expires and renews around 10:30am each day.

Why do you have a one-day lease, btw? I use three as the default.

At the time that my IP renews, windows temporarily looses it's network
connections. If windows explorer is connected to a network share, I
get a message like:
\\server\share is not accessible. You might not have permission to use
this network resource. Contact the administrator of this server to
find out if you have access permissions.
The network location cannot be reached. For information about network
troubleshooting, see Windows Help.

I've never seen this happen -but I tend to use three day leases, and have
clients log off the computer or shut it down at night.

Separately, Responsive Timelogger which accesses a DBF database on the
network crashes and disappears.
And a proprietary app connecting to a network SQL Server database
looses it's connection.

But I can immediately browse back to the network share and start the
two network database apps again.

I understood that DHCP renewals were supposed to be seamless, and not
cause disruption.

They should be....are you seeing any NACK errors in the sonicwall?

 

[Ed.]

I have been having somewhat the same problem with a Linksys BEFSR41 v2
router. My lease is 48 hrs and at expiration I get disconnected for a second
and then I am OK.

Can't find a solution. I have called Linksys and they say lower the MTU
setting. I have done so and no help. They say the router then should be sent
back and replaced. However, my router is out of warranty.

Do you think I need a new router?

I don't get NACK errors. I do get DHCPNACK messages in event viewer as
copied and pasted below. What does this mean and what can I do?

Thanks,
Ed.

Event Type: Error
Event Source: Dhcp
Event Category: None
Event ID: 1002
Date: 10/26/2004
Time: 7:23:45 PM
User: N/A
Computer: XP3200
Description:
The IP address lease 192.168.1.100 for the Network Card with network address
000C768D5724 has been denied by the DHCP server 192.168.1.1 (The DHCP Server
sent a DHCPNACK message).

"Lanwench [MVP - Exchange]"

 

[Lanwench [MVP - Exchange]]

I have been having somewhat the same problem with a Linksys BEFSR41 v2
router. My lease is 48 hrs and at expiration I get disconnected for a
second and then I am OK.

Can't find a solution. I have called Linksys and they say lower the
MTU setting. I have done so and no help. They say the router then
should be sent back and replaced. However, my router is out of
warranty.

Do you think I need a new router?

I don't get NACK errors.

Yes you do; based on what you write immediately after this.

I do get DHCPNACK messages in event viewer as
copied and pasted below. What does this mean and what can I do?

Thanks,
Ed.

Event Type: Error
Event Source: Dhcp
Event Category: None
Event ID: 1002
Date: 10/26/2004
Time: 7:23:45 PM
User: N/A
Computer: XP3200
Description:
The IP address lease 192.168.1.100 for the Network Card with network
address 000C768D5724 has been denied by the DHCP server 192.168.1.1
(The DHCP Server sent a DHCPNACK message).

DHCP renewals are supposed to be fairly seamless. Running the latest
firmware on your Linksys?

"Lanwench [MVP - Exchange]"

Why do you have a one-day lease, btw? I use three as the default.

I've never seen this happen -but I tend to use three day leases, and
have clients log off the computer or shut it down at night.

They should be....are you seeing any NACK errors in the sonicwall?

 

[Hans-Georg Michna]

Do you think I need a new router?

Ed,

yes, preferably one that is slightly more expensive than the
Linksys. -)

I do get DHCPNACK messages in event viewer

Description:
The IP address lease 192.168.1.100 for the Network Card with network address
000C768D5724 has been denied by the DHCP server 192.168.1.1 (The DHCP Server
sent a DHCPNACK message).

This looks very much like a DHCP server error to me. Can you
think of any good reason why the DHCP server should refuse
renewal?

Hans-Georg

 

[Ed.]

OK, thanks for the replies. I think I will just give up on this router and
go out and fine a better one and just replace it as the replies are
suggesting.

Thanks,
Ed.

 

[peter]

Hi,

Why do you have a one-day lease, btw? I use three as the default.

Just the way it has always been configured. I've increased this to
7200 minutes (5 days).

I've never seen this happen -but I tend to use three day leases, and have
clients log off the computer or shut it down at night.

I tend to leave my computer running - just lock it each night. If I
rebooted each day, then I'm sure that I wouldn't have this problem.

They should be....are you seeing any NACK errors in the sonicwall?

No NACK errors. But there is quite a bit of blocked outgoing traffic,
which I am addressing.

Thanks,
Peter