On Tue, Apr 30, 2002, Lior Hammer wrote about "Problem with Networking": > I have a very strange problem with networking, >... > i didn't change anything, but the connection creation (inside and outside > the LAN) is very slow. > after the connection is created, everything is normal. > when i ping this computer, i get a 'Request timed out' error message. > when i'm trying to connect to some port on this computer (for example: 25), > it takes a few minutes until i get a response, and then everything is > normal. >...
Sometimes bad nameserver configuration causes this kind of problem. When you ping an IP address, ping tries to do reverse name resolution to show you the name of the other machine. A working nameserver should return an answer almost immediately, but a badly-configured one might hang for many seconds (e.g., if it itself uses a non-existant name server). Taking long time to make a connection to telnet, ssh, smtp, and similar ports, can also be explained by a faulty nameserver. Many of these services by default try to reverse lookup the address connecting, and if this lookup hangs it appears as if the connection is hung (when the lookup finally returns, the connection continues at a normal pace). To check if this is indeed your problem, try "ping -n THEIPADDRESS" instead of just "ping THEIPADDRESS". Does this work? If the "-n" made a difference, it's your nameserver that is faulty. Check in /etc/resolv.conf which nameserver you're using. If this is not the correct explanation to your problem, refer to the quip in my signature below :) -- Nadav Har'El | Wednesday, May 1 2002, 19 Iyyar 5762 [EMAIL PROTECTED] |----------------------------------------- Phone: +972-53-245868, ICQ 13349191 |A conclusion is simply the place where http://nadav.harel.org.il |you got tired of thinking. ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
