Question

Hello.

Is there a way to modify ttl +1 on this lte router ?

Answer 1

Hello,

In order to set a custom TTL value for a mobile interface, follow these steps:

1. Login to the router's CLI.
2. Execute the following command to open rc.local file in a text editor: vi /etc/rc.local
3. Press "i" button on your keyboard to start editing the file.
4. Insert the following line: iptables -t mangle -I POSTROUTING -o wwan0.1 -j TTL --ttl-set X
5. Press "Esc" button on your keyboard and enter ":x" to save the file.
6. Execute the following command to run the sript: sh /etc/rc.local

X is a custom TTL value

Comments

This mean that all clients will have the same ttl when they will “leave“ router, and will go to lte/3g ?

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Yes, you are correct. If you only want to increase a TTL value of the outbound packets that are sent via mobile interface use the following rule:

iptables -t mangle -I POSTROUTING -o wwan0.1 -j TTL --ttl-inc X

X is an increment of TTL value.

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Is there an update or some additional steps to this?

Was not able to see any confirmation after typing ".x" that verified the file saved.

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Hello, i tried but i can't change my ttl value. I think i did all steps correct but when i send ping command on cli ttl value is 64. Someone can help me for changing ttl value on my rutx12 ?

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Try the following commands:

• /etc/init.d/firewall restart
• iptables -t mangle -I PREROUTING -i wwan0 -j TTL --ttl-set <n>
• ping 8.8.8.8

Replace <n> with your value.

Best regards,