On Tue, 2007-11-13 at 11:54 -0500, Ross S. W. Walker wrote: > 3 possible scenarios: > > 1) DNS not properly configured > > Make sure your resolv.conf is properly configured, if you are doing > DHCP look into having your resolv.conf set through it, if you are > using PPPOE you can have the ppp daemon set it too if the DNS is > passed over the ppp connection. > Don't have a resolve.conf. > 2) TCP MTU and blackhole router if PPPOE > > If you are doing PPPOE then make sure the MTU on the ppp interface > link is set to 1492 as pppoe uses 8 bytes for ppp framing. If it is > set to 1500 then some large packets will drop and the stack will > have to resend smaller and smaller till it goes through. If ICMP > need to frag messages are dropped then the connections will stall > completely. > 1492, by default. > 3) TCP scaling window and broken router > > The latest CentOS uses the TCP scaling window algorithm to the RFC > spec which some routers don't support. Some people have noticed > that this solves the problem when communicating to other hosts > over the Internet. > > sysctl -w net.ipv4.tcp_window_scaling=0 I tried it - will see. BTW, this wouldn't muck up my keyboard shortcuts, would it? I noticed that after I executed this, some of them stopped working - again. mhr