[Sheflug] D-Link DSL 300T/OpenBSD3.7/SuSE 9.2

[lesleyb <lesley.binks [at] xxxxxxxxx>]

Hello

Thought I'd relate this tale.

My ISP went off line yesterday but came back up at 11.59:43 according to 
my D-Link DSL 300T modem.

What was very strange is that I could get no route out.  I checked my 
Internet facing box (OpenBSD) and it was getting real upset with 
arplookup and arpresolve errors and all sorts of mayhem resulted when I 
tried restarting the OpenBSD network via a 'sh netstart', or soft 
rebooting or hard rebooting.  Effectively it was saying it already had 
the IP address the modem was trying to give the NiC.

Now, I did have that D-Link set to *not* use DHCP but, for some reason 
it decided it should DHCP when iot regained the cionnection from the 
ISP.  Depsite being able to access the configuration pages, and 
reconfiguring the modem to not use DHCP I was still seeing arplookup and 
arpresoolve errors on the OpenBSD box and still getting errors 
indicating the card wouldn't accept the internet address the modem was 
trying to give it, again trying with 'sh netstart' a soft reboot and a 
hard reboot in the OpenBSD box.

Things got more interesting: I could connect to the modem's interface 
via the LAN, and over my LAN I could observe the traffic on the NiC 
connected to the modem.  I had no route out; I got messages back from 
the modem telling me the modem could not find the DNS servers, but it 
the modem's system log the DNS servers were listed and correlated with 
the DNS servers I have listed on my side.  (I'm working on running DNS 
here.)

Despite several attempts to get the network up and running using either 
a fixed IP address or DHCP on the OpenBSD box no joy whatsoever.

So I unplugged the modem from the OpenBSD box and stuck it on the SuSE 
box, set the Suse NIC to DHCP and the default route to my fixed IP 
address.  I did this via YaST2->Network Devices.

Things were a bit wobbly but with a tweak of the Suse firewall I could 
get to the D-Link again.

I checked my routeing table and noticed the lan network route was still 
coming up but I wasn't getting a default route assigned.

I've had this problem before, persistent incorrect data occurring when 
having to sort out one of the D-Link's little temper tantrums.  I dipped 
into /etc/sysconfig/network and found the broadcast, ipaddress, netmask 
and network settings were still being listed in the ifcfg-eth0 file and 
I've a suspicion that SuSE 9.2 isn't too keen on you changing the 
default route too.  It saves the data for that in another file but I see 
no purpose for it to do that.

There doesn't seem to be anywhere but ifconfig to change the ifcfg-eth0 
settings for the network, netmask and broadcast addresses and I had done 
that a number of times.

I deleted the unnecessary data from the ifcfg-eth0 file, wobbled the NIC 
down and up via ifconfig and got the connectivity I was seeking.

The issues that do occur seem to be these - if you use ifconfig to alter 
your NIC IP address, netmask and broadcast address and then use route to 
alter your default route info then any available YaST2 configuration 
data is still used when building the routeing table and NIC info.

This is on SuSE 9.2 Pro.

The outage occurred in the middle of my netinstalling Debian onto my 
laptop.  I'm not sure what the God(s) have got against me having Debian 
( ;-) ) but this is the second time I have experienced problems outside 
my control when installing Debian on one of my machines.


Regards

L.


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