Question

Hi,

we are changing the mtu size from Wifi via Custom Script to 2300.
After Update to FW 00.07.03.1 this does not work any more.

The changed MTU is also forgotten after a restart.

Answer 1

Hello,

Could you provide more details on how did you set up MTU?

Which firmware did it work previously?

How is your WiFi interface configured: as an access point or a client station?

Best regards,

Comments

Hi,

in System -> Custom Scripts we got the following entries:

ifconfig qmimux0 mtu 9000

ifconfig wlan0 mtu 2300

ifconfig eth0 mtu 9000

ifconfig eth1 mtu 9000

ifconfig br-config mtu 9000

exit 0

This does not change anything in the new fw.

When I change the values with ssh, its working but not persistent after restart.

Previous FW was RUTX_R_00.07.02.7

WiFi is configured as an access point

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What firmware did you have installed before?

Did you update with Keep settings option set to on? I have attempted the command you used with a fresh install of 7.3, placed it in System -> Custom scripts, but the change was executed and it remained after device reboot. That is the purpose of data in custom scripts.

Could you try resetting your device to factory default settings?

Also, could you check if interface names, listed by ifconfig command, match the names you use in the script? 

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As spoken we used 00.07.02.7 before.

Keep settings options was on

Resetting to factory default is not an option, our project is kinda complex... i will try to restore it from backup and try again.

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already testing with 07.03.2

The script gets executed on startup, but the

ifconfig wlan0 mtu 2300 command does nothing.

I try it via cli and it works.

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I added a  "sleep 5" to the beginning of the script and removed the ifconfig qmimux0 mtu 9000 (because its not available anymore). 

Now it works! Even after startup

Maybe the startup time from the wifi is longer with the new fw version, so the script does not know the controller?

Answer 2

A Teltonika guy told me this trick for setting the MTU via CLI. This is permanently and survives a reboot:

uci add network device

uci set network.@device[-1].name=eth0

uci set network.@device[-1].mtu=9000

Comments

Updated an two other devices via the same way

On the first device the mtu was saved

on the second device the mtu was not saved.

all have the same configuration and previous fw

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When you do "uci commit" and a "/etc/init.d network restart", then with "uci show network" the MTU setting will be shown. But the GUI doesnt know anything of!

In my tests, the MTU creates a lote of trouble, special case, with a webserive at port 80, just a oneway communication could be "established". For me, it seem like the RUTOS packet split isnt working properly. So, there semms to be a really narrwo band of situations, where it works properly.

Meanwhile, I removed all MTU changes everywhere.

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unfortunately i need the mtu because some devices send large packets.

I still dont have any solution :(

i could swear that there was a possibility to change the wlan mtu directly via the gui before. with this fw its not possible anymore, maybe this is the problem?

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Could you try if the following works:

• ip link set dev wlan0 mtu 2300

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Not persistent after reboot :(

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Append the /etc/config/network configuration file with the following lines at the end:

config device
        option name 'wlan0'
        option mtu '2300'

As in the example below(I used 1800). It remained after device reboot:

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Does not work :(

The only working trick at the moment is to add a sleep 10 to the custom script..

Answer 3

so the 00.07.03.3 is the fix for it? :D

Comments

Have you tried it and did it solve the issue?

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don't have the time at the moment. :(