Intermittent DNS failure in SLED11 SP1

For some reason my SLED11 SP1 work station periodically loses its DNS.
Sometimes after going to sleep or a reboot it won’t log back into the
domain anymore. After logging in with a localhost account I can ping the
DNS server’s IP but cannot resolve its hostname. All windows machines on
the network are working fine. Sometimes DNS eventually comes back, but I
can find no rhyme nor reason to why or how.

The SLED SP1 workstation is using an Intel e1000e network card. The
driver is installed and appears to be functioning normally. It gets an
IP via DHCP automatically and detects the correct gateway and DNS
server.

Any ideas?


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

On Thu, 05 Jan 2012 20:56:02 GMT
kriswood kriswood@no-mx.forums.novell.com wrote:
[color=blue]

For some reason my SLED11 SP1 work station periodically loses its DNS.
Sometimes after going to sleep or a reboot it won’t log back into the
domain anymore. After logging in with a localhost account I can ping
the DNS server’s IP but cannot resolve its hostname. All windows
machines on the network are working fine. Sometimes DNS eventually
comes back, but I can find no rhyme nor reason to why or how.

The SLED SP1 workstation is using an Intel e1000e network card. The
driver is installed and appears to be functioning normally. It gets an
IP via DHCP automatically and detects the correct gateway and DNS
server.

Any ideas?

[/color]
Hi
Are the contents of /etc/resolv.conf have the DNS server present? Are
you using Traditional ifup or the Network Manager?


Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.1 (x86_64) Kernel 3.1.0-1.2-desktop
up 1:53, 3 users, load average: 0.07, 0.07, 0.05
CPU Intel i5 CPU M520@2.40GHz | Intel Arrandale GPU

I can confirm that it happens sometimes (not very often though, maybe
because I’m not a heavy Suspend/Hibernate user). I use Networkmanager
and system automatically connects to Internet with wifi. It actually
connects but domain names don’t work (there is DNS in resolve.conf - it
is static and the only one): I can reach websites only by ip addresses.
Reconnection usually helps. But sometimes a reboot is required.


AlexDudko

AlexDudko’s Profile: http://forums.novell.com/member.php?userid=100476
View this thread: http://forums.novell.com/showthread.php?t=450351

AlexDudko;2165659 Wrote:[color=blue]

I can confirm that it happens sometimes (not very often though, maybe
because I’m not a heavy Suspend/Hibernate user). I use Networkmanager
and system automatically connects to Internet with wifi. It actually
connects but domain names don’t work (there is DNS in resolve.conf - it
is static and the only one): I can reach websites only by ip addresses.
Reconnection usually helps. But sometimes a reboot is required.[/color]

Yes that is how it seems to be happening on my system. Usually a reboot
fixes it. I’ve found it happens less often with static IP than with DHCP
but not sure if doing so actually changed anything or if due the
intermittent nature of it, it just isn’t happening as often now.


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

Further troubleshooting:

1: I checked the resolv.conf as suggested earlier. Yes, the nameservers
appear there.

2: After switching to static IP and manually entering the nameservers
it seems I no longer have the DNS issue at all. Instead I’m getting
absolutely no network traffic whatsoever. It only occurs when logging
in. I get to the login screen and cannot log in with the domain user. I
can login with a local user. Once logged in as the local user I cannot
ping anything else on the network. Rebooting seems to put it back to a
working state most of the time.


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

On Tue, 10 Jan 2012 19:16:02 GMT
kriswood kriswood@no-mx.forums.novell.com wrote:
[color=blue]

Further troubleshooting:

1: I checked the resolv.conf as suggested earlier. Yes, the
nameservers appear there.

2: After switching to static IP and manually entering the nameservers
it seems I no longer have the DNS issue at all. Instead I’m getting
absolutely no network traffic whatsoever. It only occurs when logging
in. I get to the login screen and cannot log in with the domain user.
I can login with a local user. Once logged in as the local user I
cannot ping anything else on the network. Rebooting seems to put it
back to a working state most of the time.

[/color]
Hi
Don’t forget to add the gateway address…?


Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.1 (x86_64) Kernel 3.1.0-1.2-desktop
up 1 day 6:50, 3 users, load average: 0.07, 0.04, 0.05
CPU Intel i5 CPU M520@2.40GHz | Intel Arrandale GPU

I spoke too soon, it does still lose DNS occasionally, just not as
often. This time it happened after trying to join the domain via the
Windows Domain Membership wizard.

malcolmlewis;2166526 Wrote:[color=blue]

On Tue, 10 Jan 2012 19:16:02 GMT
Hi
Don’t forget to add the gateway address…?[/color]

Yes, I’ve assigned the gateway address.

Oh, and to answer an earlier question, I am using Network Manager.


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

I’m unsure exactly what I did last week that got it to start working
correctly, but I haven’t seen it lose connectivity in several days. Now
I’m having a different problem and not sure if I should post it in this
thread or start a new one, but for the sake of keeping things in one
place where I can find them easily I’ll just put it here.

My hostname is set, I’ve joined the domain, I’ve got connectivity to
the network, but my SLED11 SP1 machine is not showing up under the
domain in DNS on the Active Directory server. How do I get it to show up
there?


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

More info as I dig a little deeper:

Under “DHCP > nameserver.mydomain.com > IPv4 > Scope [192.168.1.0] >
Address Leases” on the nameserver’s console, the SLED11 machine shows up
with the correct IP address but without its hostname. Could this be part
of the problem? How do I get the nameserver to understand the SLED11
box’s hostname?


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

ok I added the following lines to my /etc/dhclient.conf:

send dhcp-client-identifier “myhostname”;
send host-name “myhostname”;

After doing that and restarting my network interface via network
manager the SLED machine now shows up with its hostname intact under
Address Leases. Unfortunately it still does not show up under DNS >
NAMESERVER > Forward Lookup Zones > mydomain.com


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351

I’ve solved all my networking issues now by one simple step: I disabled
Network Manager. Immediately my domain controller saw the SLED11
machine, forward and reverse DNS started working, and I’ve had no
connectivity problems since. I’m not sure what it is about Network
Manager that was causing all this trouble, but the using the traditional
ifup method seems to have resolved everything.

Thanks everyone, for all the help! Now to figure out why Altiris 7.1
isn’t seeing my SLED11 machine correctly, but that’s for a different
forum! :wink:


kriswood

kriswood’s Profile: http://forums.novell.com/member.php?userid=122184
View this thread: http://forums.novell.com/showthread.php?t=450351