Re: mtu question. more should be better, right?

2011-11-07 Thread David Newman
On 11/7/11 8:45 AM, Deric Kwok wrote: > When I setup the server mtu as 9100. why I have to configure the > switch mtu 9300 to make it working? > > What this extra 200 bytes is for what purpose? ls it standard? MTUs above 2000 bytes are nonstandard. The most recent Ethernet spec, 802.3-2008, defi

Re: mtu question. more should be better, right?

2011-11-07 Thread Iljitsch van Beijnum
On 7 Nov 2011, at 17:45 , Deric Kwok wrote: > When I setup the server mtu as 9100. why I have to configure the > switch mtu 9300 to make it working? > What this extra 200 bytes is for what purpose? ls it standard? To avoid problems you really want to set the MTU of all your IP devices on the sa

Re: mtu question

2010-11-17 Thread Pete Lumbis
I know in more recent Cisco IOS software (12.4.24T or later I think) the MTU of a GRE interface is that of the largest memory block on the box. I wouldn't be surprised if this is the same for loopbacks since they are a software concept. The logic behind this is that the largest frame the software

RE: mtu question

2010-11-17 Thread Brandon Kim
..@gmail.com; nanog@nanog.org > Subject: Re: mtu question > > On Wed, 17 Nov 2010 16:23:54 -0500 > Brandon Kim wrote: > > > > > Jack brings up a good point. MTU is basically pointless since packets never > > traverse any real interface... > > So in th

Re: mtu question

2010-11-17 Thread Mark Smith
On Wed, 17 Nov 2010 16:23:54 -0500 Brandon Kim wrote: > > Jack brings up a good point. MTU is basically pointless since packets never > traverse any real interface... > So in theory the size can be anything... > > Not quite. You hit packet length field limits. IPv4 packets can't be large

RE: mtu question

2010-11-17 Thread Brandon Kim
Jack brings up a good point. MTU is basically pointless since packets never traverse any real interface... So in theory the size can be anything... > Date: Wed, 17 Nov 2010 15:02:22 -0600 > From: jba...@brightok.net > To: deric.kwok2...@gmail.com > Subject: Re: mtu question

Re: mtu question

2010-11-17 Thread Jack Bates
On 11/17/2010 11:08 AM, Deric Kwok wrote: Hi I just see that the mtu in lo is different from standard eth 1500 Any meaning of it? You transfer huge amounts of data on loopbacks similar to sockets. Supporting large MTU's is appropriate, and given the virtual nature of loopbacks, is probably

Re: mtu question

2010-11-17 Thread Owen DeLong
I think that the MTU on LO is pretty irrelevant in general. If it does matter, larger is probably better. Owen On Nov 17, 2010, at 9:08 AM, Deric Kwok wrote: > Hi > > I just see that the mtu in lo is different from standard eth 1500 > > Any meaning of it? > > eg: > Standard eth 1500 > > in