I am trying to optimize my pppoe mtu setting, first using from cmd i found 1452 + 28 (1480) to be best but when I try same test from MT (OS Ver 3.30) is giving from “corrupted” to “packet too large and cannot be fragmented”
http://www6.nohold.net/Cisco2/ukp.aspx?pid=80&login=1&app=search&vw=1&articleid=386
Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.
C:\Users\admin>ping http://www.google.ie -f -l 1472
Pinging www-cctld.l.google.com [209.85.143.94] with 1472 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Ping statistics for 209.85.143.94:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),
C:\Users\admin>ping http://www.google.ie -f -l 1492
Pinging www-cctld.l.google.com [209.85.143.94] with 1492 bytes of data:
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Ping statistics for 209.85.143.94:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),
C:\Users\admin>ping http://www.google.ie -f -l 1452
Pinging www-cctld.l.google.com [209.85.143.94] with 1452 bytes of data:
Reply from 209.85.143.94: bytes=64 (sent 1452) time=57ms TTL=52
Reply from 209.85.143.94: bytes=64 (sent 1452) time=57ms TTL=52
Reply from 209.85.143.94: bytes=64 (sent 1452) time=58ms TTL=52
Reply from 209.85.143.94: bytes=64 (sent 1452) time=58ms TTL=52
Ping statistics for 209.85.143.94:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 57ms, Maximum = 58ms, Average = 57ms
MikroTik RouterOS 3.30 (c) 1999-2009 http://www.mikrotik.com/
/interface pppoe-client
add ac-name=“” add-default-route=no allow=pap,chap,mschap1,mschap2 comment=“”
dial-on-demand=no disabled=no interface=ether1 max-mru=1480 max-mtu=1480
mrru=disabled name=pppoe-out1 password=broadband1 profile=default
service-name=“” use-peer-dns=no user=XXXXXXXX
add ac-name=“” add-default-route=no allow=pap,chap,mschap1,mschap2 comment=“”
dial-on-demand=no disabled=no interface=ether2 max-mru=1480 max-mtu=1480
mrru=disabled name=pppoe-out2 password=broadband1 profile=default
service-name=“” use-peer-dns=no user=XXXXXXXX
[admin@Load_X] > ping http://www.google.com size=1480 do-not-fragment
209.85.143.99 92 byte ping: ttl=54 time=39 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=42 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=38 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=48 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=39 ms (corrupted)
5 packets transmitted, 5 packets received, 0% packet loss
100% replies corrupted
round-trip min/avg/max = 38/41.2/48 ms
[admin@Load_X] > ping http://www.google.com size=1452 do-not-fragment
209.85.143.99 92 byte ping: ttl=54 time=39 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=38 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=39 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=38 ms (corrupted)
209.85.143.99 92 byte ping: ttl=54 time=38 ms (corrupted)
5 packets transmitted, 5 packets received, 0% packet loss
100% replies corrupted
round-trip min/avg/max = 38/38.4/39 ms
[admin@Load_X] > ping http://www.google.com size=1492 do-not-fragment
packet too large and cannot be fragmented
packet too large and cannot be fragmented
packet too large and cannot be fragmented
packet too large and cannot be fragmented
packet too large and cannot be fragmented