Can you try and capture any ipv6 packets trying to leave your computer when 
you're trying to login into cvs or to do other things with cvs ?


IF you find anything running, disable ipv6.
(refer to your distribution's manual on how to do this.)

Cheers.




Taylan Yetkin wrote:
> Hi,
> ifconfig in the host returns:
> 
> eth0      Link encap:Ethernet  HWaddr 00:19:D1:25:1F:C9
>          inet addr:128.255.34.167  Bcast:128.255.35.255  Mask:255.255.252.0
>          inet6 addr: fe80::219:d1ff:fe25:1fc9/64 Scope:Link
>          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>          RX packets:190785 errors:0 dropped:0 overruns:0 frame:0
>          TX packets:55961 errors:0 dropped:0 overruns:0 carrier:0
>          collisions:0 txqueuelen:100
>          RX bytes:57983176 (55.2 MiB)  TX bytes:11357915 (10.8 MiB)
>          Base address:0xecc0 Memory:dffe0000-e0000000
> 
> lo        Link encap:Local Loopback
>          inet addr:127.0.0.1  Mask:255.0.0.0
>          inet6 addr: ::1/128 Scope:Host
>          UP LOOPBACK RUNNING  MTU:16436  Metric:1
>          RX packets:5670 errors:0 dropped:0 overruns:0 frame:0
>          TX packets:5670 errors:0 dropped:0 overruns:0 carrier:0
>          collisions:0 txqueuelen:0
>          RX bytes:10405386 (9.9 MiB)  TX bytes:10405386 (9.9 MiB)
> 
> while netstat -nr returns
> 
> 
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS Window  irtt 
> Iface
> 128.255.32.0    0.0.0.0         255.255.252.0   U         0 0          0 
> eth0
> 169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 
> eth0
> 0.0.0.0         128.255.32.1    0.0.0.0         UG        0 0          0 
> eth0
> 
> 
> Taylan
> 
> 
> 
> Maxim kovgan wrote:
>> Taylan Yetkin wrote:
>>> Both ping and traceroute  the host from fermi machines returns  
>>> success.  I need some time to understand the use of tcpdump.
>>> thanks,
>>> Taylan
>>
>> can you post your ifconfig of the listening interface ?
>>
>>
>> a routing table would be nice too:
>> netstat -nr
>>
>> you can of course scramble the IP addresses.
>>
>>
>>
>>>
>>> Maxim kovgan wrote:
>>>> John Summerfield wrote:
>>>>> Maxim kovgan wrote:
>>>>>> John Summerfield wrote:
>>>>>>> Taylan Yetkin wrote:
>>>>>>>> Hi,
>>>>>>>> I installed a cvs repository in my local SL machine and trying 
>>>>>>>> to connect
>>>>>>>>  it
>>>>>>>> from fermi machines. I get the following error:
>>>>>>>>
>>>>>>>> [cmswn085> cvs login
>>>>>>>> Logging in to 
>>>>>>>> :pserver:[log in to unmask]:2401/var/lib/
>>>>>>>> cvsroot
>>>>>>>> CVS password:
>>>>>>>> cvs [login aborted]: connect to
>>>>>>>> neutralino.physics.uiowa.edu(128.255.34.167):2401 failed: No 
>>>>>>>> route to hos
>>>>>>>> t
>>>>>>>
>>>>>>> This is a routing/firewall problem. the cvs command asks for the 
>>>>>>> password before trying to connect.
>>>>>>>
>>>>>>> 07:02 [summer@numbat ~]$ cvs  -d 
>>>>>>> :pserver:anoncvs@localhost:2401/var/lib/ login
>>>>>>> Logging in to :pserver:anoncvs@localhost:2401/var/lib
>>>>>>> CVS password:
>>>>>>> cvs [login aborted]: connect to [localhost]:2401 failed: 
>>>>>>> Connection refused
>>>>>>> 07:03 [summer@numbat ~]$
>>>>>>
>>>>>> It's most probably tcpwrappers
>>>>>
>>>>> No. That allows a connexion, then rejects it. You don't get "no 
>>>>> route" or "refused messages."
>>>>
>>>> AFAIK tcpwrappers refuse too.
>>>> but I somehow missed the no route to.. :)
>>>> and you're right! it needs some investigation:
>>>>
>>>> 1. ping to the host
>>>> 2. traceroute to the host.
>>>>
>>>> if you sporadically get the no route problem, it means you have ... 
>>>> a routing problem :)
>>>>
>>>> after you finished up with it, you can continue and trouble shoot.
>>>> routing problem can be cause by your university/enterprise firewall 
>>>> too.
>>>>
>>>>
>>>> you can also investigate with tcpdump, which is a great sniffer.
>>>>
>>>> Good luck!
>>>>
>>>>
>>>>
>>>>>
>>>>> "reset" is more probable.
>>>>>
>>>>>
>>>>
>>>>
>>>
>>
>>
> 


-- 
Maxim Kovgan,
Distributed Systems and Data Mining Laboratory
Computer Science, Technion
http://dsl.cs.technion.ac.il