Can't ping

Can't ping

Post by Mik » Sun, 18 May 2003 16:14:01



I am trying to set up a server. Everything looks fine but I can't ping
to anything on the Internet when I connect it to my DSL line. It was
pinging at one time but I must of changed something now I can't.

I can ping its eth0 from the console also internal machines but not
out. I have tried with and without a firewall.

I have linux 2.4.20 & Slack 9.0

Below is the route table and output of "ifconfig"

bash-2.05b# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref
Use Iface
64.7.78.60      0.0.0.0         255.255.255.252 U     0      0
0 eth0
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0
0 eth1
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0
0 lo
0.0.0.0         64.7.78.61      0.0.0.0         UG    1      0
0 eth0

-------------------------------------------------------------------------

eth0      Link encap:Ethernet  HWaddr 00:10:5A:87:E9:A6
          inet addr:64.7.78.62  Bcast:64.7.78.63  Mask:255.255.255.252
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:237 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:0 (0.0 b)  TX bytes:9954 (9.7 Kb)
          Interrupt:10 Base address:0x300

eth1      Link encap:Ethernet  HWaddr 00:50:BA:6B:ED:EC
          inet addr:192.168.0.2  Bcast:192.168.0.255
Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1260 errors:0 dropped:0 overruns:0 frame:0
          TX packets:917 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:81308 (79.4 Kb)  TX bytes:148173 (144.7 Kb)
          Interrupt:3 Base address:0x320

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:246 errors:0 dropped:0 overruns:0 frame:0
          TX packets:246 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:25887 (25.2 Kb)  TX bytes:25887 (25.2 Kb)

 
 
 

Can't ping

Post by Martin Coope » Sun, 18 May 2003 16:46:15



Quote:> eth0      Link encap:Ethernet  HWaddr 00:10:5A:87:E9:A6
>           inet addr:64.7.78.62  Bcast:64.7.78.63

Mask:255.255.255.252

Quote:>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:237 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:100
>           RX bytes:0 (0.0 b)  TX bytes:9954 (9.7 Kb)
>           Interrupt:10 Base address:0x300

Hi Mike,
    according to this, your gateway (is this a dsl router or something
else ?) is not returning data to this machine.  Can you ping the
gateway ?  The output of a traceroute to an internet site night be
more helpful in identifying the problem.  Also, check your iptables
rules with 'iptables -nL'  is there anything left in there after
disabling your firewall ?  When you say firewall, is it your own
script ?

    Martin

 
 
 

Can't ping

Post by Mik » Sun, 18 May 2003 23:45:01


I have a DSL modem. I believe my gateway is a computer at my ISP.
Can't ping the gateway or the nameserver. The firewall is something I
adapted from a sample script. When I disable, all iptables are empty
per below.

This a backup server, which I connect to the DSL line when testing
then disconnect because I have only one IP. The primary server works
fine.

Is it possible the eth0 card is bad?

------ IPTABLES with no firewall --------------

bash-2.05b# iptables -nL
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

---------------------------------------------------

Thanks

On Sat, 17 May 2003 08:46:15 +0100, "Martin Cooper"




>> eth0      Link encap:Ethernet  HWaddr 00:10:5A:87:E9:A6
>>           inet addr:64.7.78.62  Bcast:64.7.78.63
>Mask:255.255.255.252
>>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>>           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
>>           TX packets:237 errors:0 dropped:0 overruns:0 carrier:0
>>           collisions:0 txqueuelen:100
>>           RX bytes:0 (0.0 b)  TX bytes:9954 (9.7 Kb)
>>           Interrupt:10 Base address:0x300

>Hi Mike,
>    according to this, your gateway (is this a dsl router or something
>else ?) is not returning data to this machine.  Can you ping the
>gateway ?  The output of a traceroute to an internet site night be
>more helpful in identifying the problem.  Also, check your iptables
>rules with 'iptables -nL'  is there anything left in there after
>disabling your firewall ?  When you say firewall, is it your own
>script ?

>    Martin

 
 
 

Can't ping

Post by Martin Coope » Mon, 19 May 2003 00:37:04



Quote:

> I have a DSL modem. I believe my gateway is a computer at my ISP.
> Can't ping the gateway or the nameserver. The firewall is something
I
> adapted from a sample script. When I disable, all iptables are empty
> per below.

> This a backup server, which I connect to the DSL line when testing
> then disconnect because I have only one IP. The primary server works
> fine.

> Is it possible the eth0 card is bad?

Well that rules out iptables then.  Could be the ethernet card, I
assume you use the same cable with the other server, so that's ruled
out. The other possibility is that you have a dodgy device driver.
Probably the easiest thing to try is a different ethernet card.  I
have had problems with 3com cards before, take a look here
http://www.geocrawler.com/archives/3/432/1998/9/0/2239054/, it might
help.  Although most of the problems with these cards seem to be
failure to transmit.  Have you tried reseating the card in it's slot ?

    Martin

 
 
 

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