Re: [Xen-users] domU network doesn''t get IP

Jayesh Salvi
Mon, 02 Jan 2006 21:05:38 -0000

Yeah, I thought 192.168.*.* are private addresses so any will do. My ISP has
provided me a single IP address that too dynamic, so I guess I can only use
IP addresses that are reserved for private use. So now I am using
192.168.20.20 (maybe 192.168.1.1 is a special (router) address, not sure)

In addition, I tried some other thing. Instead of configuring eth0 from
inside domU I configured vifx.0 from dom0. So it looked like:

[root@orion hotplug]# ifconfig vif11.0 192.168.20.20 netmask 255.255.254.0
(I used this netmask because that''s what is set in my dom0)
[root@orion hotplug]# ifconfig vif11.0 up
[root@orion hotplug]# ifconfig
...
vif11.0   Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF
          inet addr:192.168.20.20  Bcast:192.168.21.255  Mask:255.255.254.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:9 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2169 errors:0 dropped:164 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:1878 (1.8 KiB)  TX bytes:141298 (137.9 KiB)
...

I had also updated /etc/sysconfig/network-scripts/ifcfg-eth0 as follows:
[root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
BOOTPROTO=none
ONBOOT=yes
TYPE=Ethernet
GATEWAY=24.118.198.1
IPADDR=192.168.20.20
NETMASK=255.255.254.0


Then the ping of domU from dom0 was successful, but telnet failed:
[root@orion hotplug]# ping 192.168.20.20
PING 192.168.20.20 (192.168.20.20) 56(84) bytes of data.
64 bytes from 192.168.20.20: icmp_seq=0 ttl=64 time=0.046 ms
64 bytes from 192.168.20.20: icmp_seq=1 ttl=64 time=0.031 ms
64 bytes from 192.168.20.20: icmp_seq=2 ttl=64 time=0.037 ms
64 bytes from 192.168.20.20: icmp_seq=3 ttl=64 time=0.039 ms
64 bytes from 192.168.20.20: icmp_seq=4 ttl=64 time=0.038 ms

--- 192.168.20.20 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4017ms
rtt min/avg/max/mdev = 0.031/0.038/0.046/0.006 ms, pipe 2
[root@orion hotplug]# telnet 192.168.20.20
Trying 192.168.20.20...
telnet: connect to address 192.168.20.20: Connection refused
telnet: Unable to connect to remote host: Connection refused

And this did not help the view from within domU. It still has network
unreachable.

Thanks for giving the idea about ifcfg-eth0.

Jayesh

On 1/3/06, Anand <xen.mails@gmail.com> wrote:
>
> The 192.168.1.1 was an example. You should use the ip address which you
> wanted to assign to the interface (and provided to you by your isp).
>
> Also ensure that proper gateway is setup inside
> /etc/sysconfig/network-scripts/ifcfg-eth0.
>
> No need for dhcp if you want to assign a static ip. The hostname and other
> options are not required.
>
> On 1/3/06, Jayesh Salvi < jayeshsalvi@gmail.com> wrote:
> >
> > OK. Now both firewall and SELinux are disabled. I created a domU with
> > MAC AA:00:00:00:00:11.
> > Then I did manual configuration of eth0 as you told.
> > Here is the trace:
> > [root@localhost ~]# ifconfig
> > eth0      Link encap:Ethernet  HWaddr AA:00:00:00:00:11
> >           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
> >           RX packets:895 errors:0 dropped:0 overruns:0 frame:0
> >           TX packets:7 errors:0 dropped:0 overruns:0 carrier:0
> >           collisions:0 txqueuelen:1000
> >           RX bytes:58557 (57.1 KiB)  TX bytes:2394 (2.3 KiB)
> >
> > lo        Link encap:Local Loopback
> >           inet addr: 127.0.0.1  Mask:255.0.0.0
> >           UP LOOPBACK RUNNING  MTU:16436  Metric:1
> >           RX packets:8 errors:0 dropped:0 overruns:0 frame:0
> >           TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
> >           collisions:0 txqueuelen:0
> >           RX bytes:560 (560.0 b)  TX bytes:560 (560.0 b)
> >
> > [root@localhost ~]# ifconfig eth0 192.168.1.1 netmask 255.255.255.0
> > [root@localhost ~]# ifconfig eth0 up
> > [root@localhost ~]# ifconfig
> > eth0      Link encap:Ethernet  HWaddr AA:00:00:00:00:11
> >           inet addr:192.168.1.1  Bcast: 192.168.1.255
Mask:255.255.255.0
> >
> >           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
> >           RX packets:1191 errors:0 dropped:0 overruns:0 frame:0
> >           TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
> >           collisions:0 txqueuelen:1000
> >           RX bytes:78311 (76.4 KiB)  TX bytes:2436 (2.3 KiB)
> >
> > lo        Link encap:Local Loopback
> >           inet addr: 127.0.0.1  Mask:255.0.0.0
> >           UP LOOPBACK RUNNING  MTU:16436  Metric:1
> >           RX packets:8 errors:0 dropped:0 overruns:0 frame:0
> >           TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
> >           collisions:0 txqueuelen:0
> >           RX bytes:560 (560.0 b)  TX bytes:560 (560.0 b)
> >
> >
> > Even after this I can''t see dom0 from domU. My
dom0''s IP is
> > 24.118.198.46
> >
> > So when I ping my dom0 from domU, I can''t reach it:
> > [root@localhost ~]# ping 24.118.198.46
> > connect: Network is unreachable
> >
> > When I ping the IP address 192.168.1.1 from dom0, I get
> > [root@orion xen]# ping 192.168.1.1
> > PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
> > From 10.230.64.1 icmp_seq=3 Packet filtered
> > From 10.230.64.1 icmp_seq=6 Packet filtered
> > From 10.230.64.1 icmp_seq=8 Packet filtered
> >
> > --- 192.168.1.1 ping statistics ---
> > 11 packets transmitted, 0 received, +3 errors, 100% packet loss, time
> > 10137ms
> > , pipe 2
> >
> > Thanks Anand for your suggestions so far.
> >
> > I want to clarify few more thing:
> > In my domain config file, I now set mac address myself, instead of
> > default.  So my vif is now:
> > vif = [ ''mac=aa:00:00:00:00:11, bridge=xenbr0'' ]
> > What about DHCP option? Should I turn it on/off? I tried it both ways,
> > but that didn''t help - my dom0 gets its IP by DHCP from my
ISP provider.
> > I don''t set nics, because by default it is 1.
> > I also don''t set netmask, gateway, hostname in my domain
config file.
> > Should I set these variables?
> >
> > Let me know.
> > Thanks,
> > Jayesh
> > On 1/3/06, Anand <xen.mails@gmail.com> wrote:
> > >
> > > Make sure your firewall is disabled. Disable selinux.
> > >
> > > Manual configuration of eth0 can be done as follows:
> > >
> > > ifconfig eth0 192.168.1.1 netmask 255.255.255.0
> > >
> > > ifconfig eth0 up
> > >
> > > Now try to ping the interface.
> > >
> > > Which version of xen are you using ?
> > >
> > > On 1/3/06, Jayesh Salvi < jayeshsalvi@gmail.com> wrote:
> > > >
> > > > > Try to manually configure the eth0 inside domU and see
if it
> > > > helps.
> > > > Sorry, I don''t know exactly how to do it. Could you
elaborate on how
> > > > to manually configure eth0?
> > > >
> > > > Thanks for pointing out the custom mac address question.
> > > >
> > > > Can anyone tell me about these error messages from
xend-hotplug.log
> > > >
> > > > xenstore-read: couldn''t read path
backend/vbd/5/777/physical-device
> > > > xenstore-read: couldn''t read path
backend/vif/5/0/ip
> > > > xenstore-read: couldn''t read path
backend/vif/5/0/bridge
> > > > xenstore-read: couldn''t read path
backend/vbd/5/777/physical-device
> > > > [After I shutdown the domain I further get]
> > > > xenstore-read: couldn''t read path
backend/vif/5/0/ip
> > > > xenstore-read: couldn''t read path
backend/vif/5/0/bridge
> > > > interface vif5.0 does not exist!
> > > >
> > > > I think "couldn''t read path backend/vif/5/0/ip
"  should really have
> > > > to do with this IP problem. But I don''t understand
which path is this? Is
> > > > it  a path somewhere on root file system?
> > > > On 1/3/06, Anand < xen.mails@gmail.com> wrote:
> > > > >
> > > > > >I have started domU successfully. I am using the
default
> > > > > xend-config.sxp, it uses >(network-script
network-bridge). But my
> > > > > domU doesn''t get any IP information, and
it''s >disconnected from dom0 and
> > > > > rest of the world.
> > > > >
> > > > > Try to manually configure the eth0 inside domU and see
if it
> > > > > helps.
> > > > >
> > > > > >(Also I don''t understand where the domU
gets its MAC address
> > > > > 00:16:3E:56:79:71? Could >anyone explain that as
well?)
> > > > >
> > > > > You can setup a custom mac address by using the option
vif > > > > > [''mac=FF:FE:00:18:98:FB,
bridge=xenbr0''] inside the domU config file.
> > > > > Substitute the mac address after the mac= for the
desired mac address.
> > > > >
> > > > > --
> > > > >
> > > > > regards,
> > > > >
> > > > > Anand
> > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Jayesh
> > > >
> > > >
> > >
> > >
> > > --
> > >
> > > regards,
> > >
> > > Anand
> >
> >
> >
> >
> > --
> > Jayesh
> >
> >
>
>
> --
>
> regards,
>
> Anand