I put this into my Manual Startup Commands section recently...ifconfig eth1 mtu 296
 
I've been having problems getting onto www.zdnet.com for a while now.
 
Ran across a FAQ that gave me an idea of what might be causing the problem...
 
SNIP... from http://members.home.net/ipmasq/ipmasq-HOWTO-1.65-7.html#ss7.5
 
"As of the 2.0.36 and 2.2.2 Linux kernels, there is a an elusive BUG in the Masquerade code that has problems with packets that have the DF or "Don't Fragment" bit set. Basically, when a MASQ box connect to the Internet with an MTU of anything less than 1500, some packets will have the DF field set. Though changing the MTU 1500 on the Linux box will seemingly fix the problem, the bug is still there. What is believed to be happening is that the MASQ code is not properly re-writing the returning ICMP packets with the ICMP 3 sub 4 code back to the originating MASQed computer. Because of this, the packets get dropped. "

"No worries though. A perfectly good workaround is to change your Internet link's MTU to 1500. Now some users will balk at this because it can hurt some latency specific programs like TELNET and games but the impact is only slight. On the flip site, most HTTP and FTP traffic will SPEED UP! "

Just thought anyone else might want to know in case you are suddenly having problems accessing sites after changing your mtu setting.

 

ChrisK

 

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