RB411 / Huwaei all incoming connection closed

RouterOS Beginner Basics
1

Problem is that my ADSL line is down and I need to set up a GSM/Edge line up until the ADSL is up again.

In the RB411U with the Huwaei /O2 modem I have succesfully connected to the internet and everything is working except the server. All connection from outside seems to be blocked. I have oppened the the needed ports in the firewall and the forward is set up in NAT. This set up works fine on the RB750. But when setting up the same rules in the RB411 with the GSM connection all traffic on these two ports are still blocked.

Can I somehow work around this problem and åbne for the incoming traffice to the server?

Thanks,

Pilgrim

2

Do you have public IP address assigned by your GSM company?
What port do you want to connect to?
I’m asking you because in my country (Poland) GSM connections are NAT-ed
and IP address is assigned from private network (mostly 172.x.x.x).

Regards, Grzegorz.

3

The provider is O2 telefonica in the Czech Republic.
Ip has changed a couple of times since i connected an now it is 85.162.17.xxx. Seems to belong to Eurotel.cz, which I believe is the company telefonica aquired.

The ports is need to open is are two port for a server that I am hosting the ports are random choosen and I have just taken two ports in the range from 600 to 700. and opened these two ports in the firewall and made the forward in nat using PPP interface as in-interface and dst-nat to the server IP. Work all fine when connected by ADSL/RB750. So that is why I am wondering if there could be any added security on the mobile internet that doesn’t allow any incoming traffic not initiated from the LAN side.

I have also tried to set up an FTP and open port 21, but with the same result.

Thanks,

Pilgrim

4

there could be any added security on the mobile internet that doesn’t allow any incoming traffic not initiated from the LAN side.

You are right, incoming traffic from WAN to privileged ports is probably blocked.
Try to set your incoming ports to unprivileged (> 1024) ones.

Hope this helps, Grzegorz.

5

Thanks Grzegorz.

Seems that everything is blocked. I tried to change the ports to 7xxx and the result is the same. I will try to get hold of O2 today to see if they can confirm if incoming traffic is blocked.

In case that the incoming traffic is really blocked, is there then a workaround?

Thanks,

Pilgrim

6

Hi,

IMHO GSM companies offer ‘surf web/read email’ service only :frowning: .
Visit this site http://www.grc.com and select ‘Shields UP!’ from ‘Services’ menu.
This will test what ports are open for your public IP address.
If everything is blocked there is no workaround for this :frowning: .

Regards, Grzegorz.

7

You were right about the provider is blocking the incoming traffic. I talked to O2 and it turns out that everything is blocked in the standard subscription, but they were able to offer another APN where incoming raffic is open. They changed my subscription (same price and condition, they just changed it to “scpecial” that allows me access to the open APN) so now I have open incoming traffic and a static IP :slight_smile:

rgs Pilgrim