How to find out MTU Size
Here is the Bat file program.
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echo off
set mtu=300
set IPADDR=192.168.1.1
echo Target IPAddress is %IPADDR%
rem ontime Check
ping %IPADDR% | find "ms TTL" > NUL
if ERRORLEVEL 1 goto err
rem 100MTU Check
:check1
echo try DataSize: %mtu%
ping -f -l %mtu% %IPADDR% | find "ms TTL" > NUL
if ERRORLEVEL 1 goto check2
set /a mtu = mtu + 100
goto check1
pause
rem 50MTU Check
:check2
echo DataSize: %mtu% is Failed.
set /a mtu = mtu - 50
echo try DataSize: %mtu%
ping -f -l %mtu% %IPADDR% | find "ms TTL" > NUL
if ERRORLEVEL 1 (
echo DataSize: %mtu% is Failed.
set /a mtu = mtu - 50
)
goto check3
pause
rem 10MTU Check
:check3
set /a mtu = mtu + 10
echo try DataSize: %mtu%
ping -f -l %mtu% %IPADDR% | find "ms TTL" > NUL
if ERRORLEVEL 1 (
echo DataSize: %mtu% is Failed.
set /a mtu = mtu - 10
goto check4
)
goto check3
pause
rem 1MTU Check
:check4
set /a mtu = mtu + 1
echo try DataSize: %mtu%
ping -f -l %mtu% %IPADDR% | find "ms TTL" > NUL
if ERRORLEVEL 1 goto result
goto check4
pause
rem Result Display
:result
rem IP headder 8byte {ICMP headder 20byte 28byte
rem Success data size(mtu-1) {28byte MTU size calicurate.
echo DataSize: %mtu% is Failed.
set /a mtu = mtu + 27
echo Check Complete!!
echo ---------------------------------------------
echo MTU is %mtu%.
echo ---------------------------------------------
echo on
pause
exit
rem ping doesn't reach
:err
echo ---------------------------------------------
echo Ping doesn't work. Not reach to target IP address.
echo To make sure Netwrok connection again.
echo ---------------------------------------------
echo on
pause
exit
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Bat file running example.