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Re: [MiNT] Mintnet success ?

The MTU of ethernet is 1500. Under will definitely work fine, but you will incur more overhead. Sounds to me like you're ahead of the game though seeing as how it's actually working. I don't think this is negotiable when it comes to setting it higher though :-P The fact that it's working indicates an undersized/corrupted buffer somewhere (or perhaps a defect with the card). 

Thanks,
Mark


Peter Slegg wrote:

Hi all,

Ekkehard has been good enough to help me investigate my
problem sending emails and ftp'ing files up to my server.

He suggested changing the mtu size to 8k since it looked
like this

lo0:    flags=0x4b<UP,BROADCAST,LOOPBACK,RUNNING>
        inet 127.0.0.1 netmask 255.255.255.0 broadcast 127.0.0.255
        metric 0 mtu 16384
        in-packets  4 in-errors  0 collisions 0
        out-packets 4 out-errors 0
rtk0:   flags=0x43<UP,BROADCAST,RUNNING>
        inet 192.168.0.201 netmask 255.255.255.0 broadcast 192.168.0.255
        metric 0 mtu 1500
        in-packets  71 in-errors  0 collisions 0
        out-packets 120 out-errors 8


However when I tried this it didn't work.

bash-2.05a# ifconfig rtk0 addr 192.168.0.201 netmask 255.255.255.0
            broadaddr 192.168.0.255 mtu 2000 up > /dev/null
bash-2.05a# ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1): 56 data bytes
ping: sendto: Network is unreachable

I wasn't sure what was wrong so I changed rc.net thus:

ifconfig $intrfc addr $ipaddr netmask $netmask broadaddr $broadaddr
 mtu 8000 up > /dev/null 2>&1

With this it can ping devices but this didn't fix the network problem.
So out of curiosity I tried setting mtu to something less than 1500,
just 1000.

Amazingly, I was able to send a large email (50k ish) and ftp
some large files.

I now have it set to 1300 and I am able to work normally.

A year or so ago, I reported that I couldn't ping with a packet
size greater than 1500. Is this possibly related ?  It seems
to me that there is some problem with packet sizes.
Could someone try setting mtu bigger than 1500.

Regards,

Peter