Traceroute Problem - Mandrake 10.1 [solved]

[sorocco]

hello..

I am ON mandrake 10.1 , just installed few days back and it is now connected in my lan with 2 pc;s (windows xp pro ), my problem is when i try to give command traceroute any_WAN_IP ...it shows my adsl modem/router as first hoope and than ..*** ..for next forthcomming 30 hops. at the same time i am getting response from my windows pc no problem at all....ii am able to ping the same IP ..no DNS probllem ...any idea about this ?

my lan connection is as : adsl modem/router (192.168.1.1 )--->> linksys access point (192.168.2.1) acting as DHCP --->> PC!,PC2 and Mandrake PC

all the PC's are on DHCP.

see the logs ..

traceroute: unknown host google.comm

[root@localhost root]# traceroute google.com

traceroute: Warning: google.com has multiple addresses; using 72.14.207.99

traceroute to google.com (72.14.207.99), 30 hops max, 38 byte packets

1 192.168.1.1 (192.168.1.1) 1.541 ms 1.082 ms 1.048 ms

2 * * *

3 * * *

4 * * *

[root@localhost root]# ping google.com

PING google.com (64.233.187.99) 56(84) bytes of data.

64 bytes from jc-in-f99.google.com (64.233.187.99): icmp_seq=2 ttl=237 time=383 ms

64 bytes from jc-in-f99.google.com (64.233.187.99): icmp_seq=3 ttl=237 time=383 ms

64 bytes from jc-in-f99.google.com (64.233.187.99): icmp_seq=4 ttl=237 time=384 ms

 

Thanks

[ianw1974]

As far as I know, this is normal nowadays for traceroute. Are you saying traceroute works in Windows but not in Linux? Or are you saying that Windows is working properly in that it can make DNS queries and access the internet? And that your Linux machine cannot?

[sorocco]

you can see from log ..i am able to ping from my mandrake box but not traceroute ..and i can browse the net too.. with no problem at all....at the same time my windows xp machines are doing tracert ...why not mandrake ..???....i am reaching my default gateway (dsl modem/router ) but after gateway just stars..

[Greg2]

It appears to be a firewall blocking the unsolicited UDP?

 

Use ICMP ECHO instead of UDP datagrams, do

traceroute -I google.com

[sorocco]

thax..

its working now ..so every time i have to add this -I in command ..???

[Greg2]

thax..

its working now ..so every time i have to add this -I in command ..???

If you do

cat /etc/services |grep traceroute

you will find:

traceroute 33434/tcp

traceroute 33434/udp

 

What's happening is that udp/ip is the default traceroute in Linux and Unix.

 

From man traceroute:

Traceroute utilizes the IP protocol ‘time to live'

field and attempts to elicit an ICMP TIME_EXCEEDED response from each

gateway along the path to some host.

Your router is probably configured to discard all packets begging for "TIME_EXCEEDED", or discard all "TIME_EXCEEDED" ICMP traffic.

 

You may be able to upgrade your router (gateway) firmware to correct this? Or call the manufacturer of the router and ask them for help in resolving this.

 

Or you could just use the -I option. :)

[sorocco]

thax greg2 ..

right now i am not able to get you completly ..but its a nice explanation.