On a Linux router, ftp& telnet works but ping doesn't work .

On a Linux router, ftp& telnet works but ping doesn't work .

Post by Pete » Thu, 06 Sep 2001 06:34:28



Hi all

I am setting up a Linux router with a Redhat 6.2 machine (But it has a
specially made Linux 2.4 kernel) with two Intel Pro/100+ cards. The
card at eth0 has an ip address of 192.168.150.177 and it is connect to
a switch with subnet 192.168.150.160/27. The eth1 card
(192.168.150.193) is connected to a hub and this network has the
subnet of 192.168.150.192/28. A host machine with an Intel Pro/100+
card and an ip address of 192.168.150.194 is also connected to the
hub. From the router machine, I can ping and telnet into the
192.168.150.194 host machine. However, I cannot ping from the
192.168.150.194 machine to the router(192.168.150.193). But oddly, I
can ftp and telent????? Have anyone experienced this problems before.
Also, both machine connecting to the hub are connect to the regular
port (No uplink). Thank you

Peter

 
 
 

On a Linux router, ftp& telnet works but ping doesn't work .

Post by Axel Hinrich » Thu, 06 Sep 2001 07:03:35



> Hi all

> I am setting up a Linux router with a Redhat 6.2 machine (But it has a
> specially made Linux 2.4 kernel) with two Intel Pro/100+ cards. The
> card at eth0 has an ip address of 192.168.150.177 and it is connect to
> a switch with subnet 192.168.150.160/27. The eth1 card
> (192.168.150.193) is connected to a hub and this network has the
> subnet of 192.168.150.192/28. A host machine with an Intel Pro/100+
> card and an ip address of 192.168.150.194 is also connected to the
> hub. From the router machine, I can ping and telnet into the
> 192.168.150.194 host machine. However, I cannot ping from the
> 192.168.150.194 machine to the router(192.168.150.193). But oddly, I
> can ftp and telent????? Have anyone experienced this problems before.
> Also, both machine connecting to the hub are connect to the regular
> port (No uplink). Thank you

> Peter

Can you still telnet and ftp, if you disconnect eth0? If so it sounds like
a strange firewall setting (otherwise like a very strange routing problem).
First try:

echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all
echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts

(Which are the default values)

--
hinrichs at xbits dot de

 
 
 

On a Linux router, ftp& telnet works but ping doesn't work .

Post by Pete » Fri, 07 Sep 2001 02:13:52




> > Hi all

> > I am setting up a Linux router with a Redhat 6.2 machine (But it has a
> > specially made Linux 2.4 kernel) with two Intel Pro/100+ cards. The
> > card at eth0 has an ip address of 192.168.150.177 and it is connect to
> > a switch with subnet 192.168.150.160/27. The eth1 card
> > (192.168.150.193) is connected to a hub and this network has the
> > subnet of 192.168.150.192/28. A host machine with an Intel Pro/100+
> > card and an ip address of 192.168.150.194 is also connected to the
> > hub. From the router machine, I can ping and telnet into the
> > 192.168.150.194 host machine. However, I cannot ping from the
> > 192.168.150.194 machine to the router(192.168.150.193). But oddly, I
> > can ftp and telent????? Have anyone experienced this problems before.
> > Also, both machine connecting to the hub are connect to the regular
> > port (No uplink). Thank you

> > Peter

> Can you still telnet and ftp, if you disconnect eth0? If so it sounds like
> a strange firewall setting (otherwise like a very strange routing problem).
> First try:

> echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all
> echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts

> (Which are the default values)

Hi.. I already have these values set. Ping works for the original
network but not the new network I've created. (Ping works for the eth0
card, 192.168.150.177, but not the eth1 card, 192.168.150.193.) This
is indeed a very wierd problem. Can you think of any reason?
 
 
 

On a Linux router, ftp& telnet works but ping doesn't work .

Post by Joe Beckma » Sun, 09 Sep 2001 12:38:52


Do you have your firewall setup to allow ICMP traffic?  I had a similar
problem (PING & TRACEROUTE wouldn't work).  Try opening up ICMP
communications.

- Joe




> > > Hi all

> > > I am setting up a Linux router with a Redhat 6.2 machine (But it has a
> > > specially made Linux 2.4 kernel) with two Intel Pro/100+ cards. The
> > > card at eth0 has an ip address of 192.168.150.177 and it is connect to
> > > a switch with subnet 192.168.150.160/27. The eth1 card
> > > (192.168.150.193) is connected to a hub and this network has the
> > > subnet of 192.168.150.192/28. A host machine with an Intel Pro/100+
> > > card and an ip address of 192.168.150.194 is also connected to the
> > > hub. From the router machine, I can ping and telnet into the
> > > 192.168.150.194 host machine. However, I cannot ping from the
> > > 192.168.150.194 machine to the router(192.168.150.193). But oddly, I
> > > can ftp and telent????? Have anyone experienced this problems before.
> > > Also, both machine connecting to the hub are connect to the regular
> > > port (No uplink). Thank you

> > > Peter

> > Can you still telnet and ftp, if you disconnect eth0? If so it sounds
like
> > a strange firewall setting (otherwise like a very strange routing
problem).
> > First try:

> > echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all
> > echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts

> > (Which are the default values)

> Hi.. I already have these values set. Ping works for the original
> network but not the new network I've created. (Ping works for the eth0
> card, 192.168.150.177, but not the eth1 card, 192.168.150.193.) This
> is indeed a very wierd problem. Can you think of any reason?

 
 
 

1. IP Masq - Ping & Telnet ok, but HTTP & FTP don't work

Hi All,

I have a strange problem with using IP Masq.  The
Linux box (Slackware 7) is set up as a gateway to
a DSL connection.  I've gone over (and over) the
howto's/FAQ's, and the setup appears fine, but
the problem persists...

I can ping and telnet to the world from all the
Masq'd computers, but can't get to any web or ftp
sites, not even when sitting at the gateway
machine using lynx.

From all the testing/FAQ's I've read, it seems
that if ping and telnet work, so should http &
ftp.  Is that correct?  If so, then it doesn't
matter what modules I have loaded, right?

Is there a separate module for http?

I'm using ipfwadm rather than ipchains, because I
didn't realize at the time that ipchains is the
way to go for kernel 2.2.x.  I'll change that
tonight, but I don't see why that would matter.

Anyway, this is my first attempt at setting up a
gateway like this, so it quite possible that I'm
missing something really silly.

If any of you can get me pointed in the right
direction, I'd really appreciate it!

Sent via Deja.com http://www.deja.com/
Before you buy.

2. Why sez "bash: /dev/null: Permission denied" ???

3. ping works, telnet/ftp doesn't

4. text editor

5. 98 telnet doesn't work but ftp works

6. waitpid() does not wait for child to exit

7. telnet & samba work, but ftp doesn't

8. mkfs problem

9. no www, no ftp, no telnet but ping and name resolution working after router installation

10. Desparation: Linux & Win Networking - ping doesn't work

11. Ping works, telnet doesn't

12. Ping works but telnet doesn't

13. ping works, telnet doesn't