I’ve recently upgraded both of my desktop machines to opensuse 11.0. I can ping machine A from machine B, but I can’t ping machine B from machine A; when I try the latter, I receive a ‘unknown host’ error.
At the same time, if I run nslookup from either machine, it succeeds for A in both cases, and fails for machine B in both cases.
I am clueless when it comes to networking, and would refer to remain that way. With opensuse 10.x, I just booted both machines, and the commands above simply worked without any intervention from me.
The Network Settings on both machines are identical, as are /etc/hosts, /etc/dhclient.conf and /etc/resolve.conf.
SixDegrees wrote:
> I’ve recently upgraded both of my desktop machines to opensuse 11.0. I
> can ping machine A from machine B, but I can’t ping machine B from
> machine A; when I try the latter, I receive a ‘unknown host’ error.
>
> At the same time, if I run nslookup from either machine, it succeeds
> for A in both cases, and fails for machine B in both cases.
>
> I am clueless when it comes to networking, and would refer to remain
> that way. With opensuse 10.x, I just booted both machines, and the
> commands above simply worked without any intervention from me.
>
> The Network Settings on both machines are identical, as are /etc/hosts,
> /etc/dhclient.conf and /etc/resolve.conf.
>
>
-----BEGIN PGP SIGNATURE-----
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ip addr sh
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
inet 127.0.0.2/8 brd 127.255.255.255 scope host secondary lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether 00:11:2f:96:ea:bb brd ff:ff:ff:ff:ff:ff
inet 192.168.1.105/24 brd 192.168.1.255 scope global eth0
inet6 fe80::211:2fff:fe96:eabb/64 scope link
valid_lft forever preferred_lft forever
ip route sh
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.105
127.0.0.0/8 dev lo scope link
default via 192.168.1.1 dev eth0 proto static
These are both from the “B” machine, the one that seems to be missing it’s hostname. I’ll put up the results from the other machine shortly, in another post.
From the “A” machine, which is both pingable and nslookup’able:
ip addr sh
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
inet 127.0.0.2/8 brd 127.255.255.255 scope host secondary lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 100
link/ether 00:19:d1:37:71:90 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.128/24 brd 192.168.1.255 scope global eth0
inet6 fe80::219:d1ff:fe37:7190/64 scope link
valid_lft forever preferred_lft forever
ip route sh
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.128
127.0.0.0/8 dev lo scope link
default via 192.168.1.1 dev eth0 proto static
Well, everything looks pretty good there. The nslookup-able-ness of one
box doesn’t really matter if we can’t ping and nothing is blocking the
ping… the issues probably aren’t related much.
So let’s get a little more data… first, post the contents of
/etc/resolv.conf from each. Second, can you somehow get the
IP/gateway/netmask/network data from your router or modem that connects
you to the outside world? Can either machine ping www.google.com or
192.168.1.1 directly? Finally we can try to watch traffic quickly using
tcpdump if you’re up to that… not too terrible usually.
Good luck.
SixDegrees wrote:
> From the “A” machine, which is both pingable and nslookup’able:
>
> ip addr sh
> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
> link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
> inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
> inet 127.0.0.2/8 brd 127.255.255.255 scope host secondary lo
> inet6 ::1/128 scope host
> valid_lft forever preferred_lft forever
> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast
> qlen 100
> link/ether 00:19:d1:37:71:90 brd ff:ff:ff:ff:ff:ff
> inet 192.168.1.128/24 brd 192.168.1.255 scope global eth0
> inet6 fe80::219:d1ff:fe37:7190/64 scope link
> valid_lft forever preferred_lft forever
> -------------------------------------------------------
> ip route sh
> 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.128
> 127.0.0.0/8 dev lo scope link
> default via 192.168.1.1 dev eth0 proto static
>
>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2 (GNU/Linux)
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IP: 192.168.1.1
Gateway: 0.0.0.0
Netmask: 255.255.255.0
Local DNS: 0.0.0.0
Not sure what else you’re looking for here.
Yes, I can ping www.wherever.what; I can also ping the router, either through IP address or router name.
New information: I rebooted machine “A” and it is now experiencing the same problem; it’s hostname is gone from the router, and I can no longer ping it. Earlier, it had been running Windows, and I rebooted into Linux; this time, it had been shut off for a while and I booted directly into Linux, so it may be that Windows is doing something right (for a change) while Linux isn’t.
I read about editing /etc/dhclient.conf and adding
send host-name “computer_name”;
but that made no difference. It seems that the hostname isn’t being sent to the router, but I’m an idiot on this topic.
The problem seems to be that I was using NetworkManager. I shut it off and switched to using ifup, and the problem cleared up on both machines. Not sure why it was working before, as I don’t remember choosing NM. But for now, problem solved.
My son’s laptop connects fine over the wireless network, and is pingable and visible from anywhere else on the network, but he’s running Windows. I wonder if the laptop were running Linux with NM if it would be recognized?
A problem for another day. Thanks for all your help.