Cannot ping to, telnet to, but CAN use WWW from new linux box
 

Hi,

I just installed Linux on a box and am having troubles getting it configured properly for the network. I'm running Mandrake 9.1. I've put it on my network at work and can ping my Windows box from the Linux box. I can get out onto the internet. I can telnet into a Sun box from the Linux box. But, I can't see the Linux box on the network. I tried to have it ping itself, with no luck:

ping localhost

100% packet loss

Here's the results of ifconfig:

eth0 Link encap:Ethernet HWaddr 00:04:75:86:D7:5A
inet addr:192.168.1.55 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:805 errors:0 dropped:0 overruns:1 frame:0
TX packets:7 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:69413 (67.7 Kb) TX bytes:552 (552.0 b)
Interrupt:17 Base address:0xd800

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:512 errors:0 dropped:0 overruns:0 frame:0
TX packets:512 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:33582 (32.7 Kb) TX bytes:33582 (32.7 Kb)

WAIT!!! HALLEELUIA! I fixed the ping problem. In the file /etc/sysctl.conf I commented out the line net.ipv4.icmp_echo_ignore=1 and replaced it with net.ipv4.icmp_echo_ignor = 0

So, I can ping the linux box. WOO HOO!!!!

I still can't telnet to it. Here's what I've done to identify problems using telnet:

ps -ef | grep inet

root 10569 1 0 15:17 ? 00:00:00 xinetd -stayalive -reuse -pidfile /var/run/xinetd.pid

So, the daemon is up that should listen for telnet sessions, so what's the deal? What can I do to identify the problem?

Thanks,

One thing to check, are you running a firewall? Mandy 9.1 comes with shorewall. I am not exactly sure what the default is for the standard installation.

Check to see if it is running - as root - shorewall status
If it is, check the /etc/shorewall/policy and /etc/shorewall/rules to see if telnet is allowed.

Hope this helps,

PhilD

EDIT:
Also, if it is getting rejected by the firewall, you should have entries in the /var/log/messages file.

No firewall is running. I just checked. I don't have shorewall either, although I will be looking to set up a firewall in the near future.

also check and see if telnet server is enabled in the /etc/xinetd.d directory

Use Guarddog for a nice frontend to iptables :)

How do I check if telnet is enabled in the xinetd.d directory? I listed the directory and got:

chargen
chargen-udp
cups-lpd
cvs
daytime
daytime-udp
echo
echo-udp
fam
linuxconf-web
proftpd-xinetd
rsync
servers
services
sshd-xinetd
time
time-udp
xadmin

i am sorry buddy, all the while i was thinking about ftp server. i am really sorry.

it must be the iptables i guess. even though you dont have a firewall if you installed iptables and if the service is running then the dafault policy is set to drop.

so check if the service is running, if it is then do

'/etc/rc.d/init.d/iptables stop'

Well, it can't be iptables, because I don't have it in man pages or in /etc/rc.d/init.d/ directory. What's the name of the telnet daemon? How I know if xinetd can start/stop it?

Have you got the telnet-server package installed?

I do I check if the telnet package is installed? I assume I do as I did a server installation, but I'd still like to know how to check.

if you are using a rpm based system, redhat or mandrake do

rpm -qa |grep telnet


and see if there is a telnet server installed.

rpm -qa | grep telnet produced:
telnet-client-krb5-1.2.7-1mdk
gnome-telnet-2.4-4mdk

you dont have a telnet server installed. install the telnet server rpm from the cd's or download the rpm and install it.

once you install it the default is disable i guess, so you need to enable it. read the man pages for it and you can do it

I'm real new, so please bear with me. I've found telnet-server-krb5-1.2.7-mdk.i586.rpm on one of the CDs. How do I install it?

goto the directory where cdrom is mounted then

rpm -ivh telnet-serverxxxxxxxxx.rpm

man rpm for more options

you have to learn one thing and very important thing

then universal command "man";)