[tlug] [Semi-OT] Network connectivity diagnosis

[Nguyen Vu Hung <vuhung@example.com>]

Hello all,

Attached is my network[1]. "Server 123" running Samba 3.0.33 under CentOS 5.4.
All the clients on the right run Windows XP which are connected to each other by
four hubs (refer to the network map).

The symptom is that *sometimes*[2], Client #1, Client #2, Client #3 cannot connect
to the Samba server.

Because Client #3 has connectivity problem[3] so it could be a problem on Hub #2.
However, the problem could be the Samba server itself (just a guess).

The annoying thing is the issue happens randomly and I want to point out which node
in my network cause the problem.

My questions are:

1) How to determine which node cause the problem?
2) What tool and or methodology should I use?

Any help would be highly appreciated.

[1]: http://farm5.static.flickr.com/4058/4302271477_7938ae0962_o.png
[2]: A few times a day.
[3] Timed out but the connectivity resumes shortly (a few seconds and sometimes a few minutes)

-- 
**********************************************************************

Viet Nhat General Joint Stock Company (Vinicorp)

Add:  3F, 92 Hoang Ngan - Trung Hoa - Cau Giay - Hanoi

Tel :(+84)-4-3556-3607 Fax :(+84)-4-3556-3608 

Nguyen Vu Hung

Email: vuhung@example.com Mobile: (+84)-167-252-5834

***********************************************************************