----- Original Message ----- From: "Kelsey Hartigan Go" <[EMAIL PROTECTED]> To: "Philippine Linux Users Group Mailing List" <[EMAIL PROTECTED]> Sent: Monday, March 29, 2004 7:04 PM Subject: Re: [plug] setting MTU for gigabit ethernet cards
> Yes...Ethernet maximum MTU is 1508. standard ethernet mtu is 1500 bytes while for extended ethernet mtu is 9000 (jumbo frame for gigabit nics)... standard ethernet frame size is 1518 bytes (14 bytes for ethernet header + 1500 bytes mtu or payload + 4 bytes for crc)... with 802.1q vlan tagging... its ethernet frame size is 1522 bytes ( 1518 bytes + 4 bytes for vlan tagging) > On Mon, 29 Mar 2004, plug bert wrote: > > > Hello All! > > > > i've set up two rh9 linux boxes with Linksys > > gigabit cards connected via a 1 meter UTP CAT5 > > crossover cable...but the best speed/bandwidth i could > > get out of them was 272Mbps(according to iperf). i'm > > thinking that i need to tweak the TCP/IP MTU settings > > to get better performance, i.e. making it larger than > > 1500. > > > > However, whenever i try setting it to >1500, via > > ifconfig or ip net link set eth1 mtu 2000, i always > > get an "invalid argument" error. There seems to be a > > hard limit of 1500 set somewhere(i first noticed this > > when setting the MTU on iperf didn't work)...problem > > is, i don't know where B). Any suggestions? > > > > i plan to use the gigabit link for backing up data > > from one pc to the backup pc. if your linksys nic supports jumbo frame then at root just type "ifconfig eth0 mtu 9000" for maximum performance... fooler. -- Philippine Linux Users' Group (PLUG) Mailing List [EMAIL PROTECTED] (#PLUG @ irc.free.net.ph) Official Website: http://plug.linux.org.ph Searchable Archives: http://marc.free.net.ph . To leave, go to http://lists.q-linux.com/mailman/listinfo/plug . Are you a Linux newbie? To join the newbie list, go to http://lists.q-linux.com/mailman/listinfo/ph-linux-newbie
