Can't Navigate My LAN Or Ping

[Leonard Chatagnier]

-- On Sat, 12/6/08, Mark Kirkwood <markir at paradise.net.nz> wrote:

> From: Mark Kirkwood <markir at paradise.net.nz>
> Subject: Re: Can't Navigate My LAN Or Ping
> To: "Ubuntu user technical support, not for general discussions" <ubuntu-users at lists.ubuntu.com>
> Date: Saturday, December 6, 2008, 6:06 PM
> Mark Kirkwood wrote:
> >
> > Immediately after posting I noticed that both your
> wired (eth0) and 
> > wireless (wlan0) interfaces are using the 192.168.1.0
> network. This 
> > strikes me as a likely source of problems.
> >
> > Here is the equivalent output from my Ubtuntu laptop:
> >
> > [markir at zul:~]$ netstat -Frn
> > Kernel IP routing table
> > Destination     Gateway         Genmask         Flags 
>  MSS Window  
> > irtt Iface
> > 192.168.1.0     0.0.0.0         255.255.255.0   U     
>    0 0          
> > 0 wlan0
> > 169.254.0.0     0.0.0.0         255.255.0.0     U     
>    0 0          
> > 0 wlan0
> > 0.0.0.0         192.168.1.1     0.0.0.0         UG    
>    0 0          
> > 0 wlan0
> >
> > i.e no eth0 - if I  specifically list  lwan0 and eth0
> setup, I see 
> > that eth0 is unconfigured (as it should be...):
> >
> 
> Hmm, maybe scratch at least some of that - it probably just
> means your 
> lan cable is plugged in. I walked my laptop over to the
> router and 
> plugged a lan cable in and now I get something more like
> what your 
> output was:
> 
No, this machine is never plugged into the router, but I may 
have manually setup the NIC in the past.  And my router has
no wired computer on it now as it's in the shop.  Maybe Karl
is right that the router/modem has to have a wired connetion
hooked up to address the router/gateway IP.  I'm about to
wire my wireless into the router and see if I can ping the router.
It'll make Karl feel goog if he was right about that.-:))
BTW, having both wifi and eth0 manually set up has been
that way for a long time and I was aware of no problems.
But since I wasn't trying to ping the router then and have always
been able to get online, i may not have been aware of an issue.
Hope Karl's right in this case.

> [markir at zul:~]$ netstat -Frn
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS
> Window  irtt 
> Iface
> 192.168.1.0     0.0.0.0         255.255.255.0   U         0
> 0          0 
> eth0
> 192.168.1.0     0.0.0.0         255.255.255.0   U         0
> 0          0 
> wlan0
> 169.254.0.0     0.0.0.0         255.255.0.0     U         0
> 0          0 
> eth0
> 0.0.0.0         192.168.1.1     0.0.0.0         UG        0
> 0          0 
> eth0
> 
> 
> However, I do notice that you have your gateway attached to
> *both* eth0 
> and wlan0 - i.e your last 2 lines:
> 
> 0.0.0.0         192.168.1.254   0.0.0.0         UG        0
> 0          0 
> wlan0
> 0.0.0.0         192.168.1.254   0.0.0.0         UG        0
> 0          0 
> eth0
> 
> 
> whereas my machine has only 1 entry - and it changes from
> being attached 
> to wlan0 when I'm using the wireless to eth0 when I
> plug in a lan cable 
> (this machine is running Intrepid). This could well be a
> source of trouble.
> 
You could be right as I have two desktops and no laptop.  But
my computers have always used the same gateway.  Resolv.conf
has always dad the same nameserver which is the gateway IP when
using DHCP.  My gut feel is it's not a problem as both computers
have had the same gateway on DHCP and static setups.
> regards
> 
> Mark
> 

Leonard Chatagnier
lenc5570 at sbcglobal.net


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