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dsl problems need advice

Posted: Thu Jun 14, 2007 6:05 am
by illiniwireless
I currently have 4.5 meg backbone and added a dsl line to one of my towers to speed things up and have a redundunt route to take if one fails. My first problem is that I am unable to access my dsl modem through the rb532. Here is my setup.
Flags: X - disabled, A - active, D - dynamic,
C - connect, S - static, r - rip, b - bgp, o - ospf
0 ADC ether8
1 ADC ether1
2 ADC ether3
3 ADC ether7
4 ADC ether3
5 ADC ether3
6 ADC ether2
7 A S r ether1
8 S r 2 ether8

[admin@MikroTik] ip> address print
Flags: X - disabled, I - invalid, D - dynamic
0 ether2
1 ether3
2 ether3
3 ether3
4 ether1
5 ether8
6 ether7

[admin@MikroTik] ip firewall nat> print
Flags: X - disabled, I - invalid, D - dynamic
0 chain=srcnat src-address= action=masquerade

1 chain=srcnat src-address= action=masquerade

2 chain=srcnat src-address= action=masquerade

3 chain=srcnat src-address= action=masquerade

4 chain=srcnat src-address= action=masquerade

5 X chain=dstnat dst-address= protocol=tcp dst-port=59162
action=dst-nat to-addresses= to-ports=80

6 chain=dstnat dst-address= protocol=tcp dst-port=59111
action=dst-nat to-addresses= to-ports=80

What other settings do I need to get access. When I'm trying to gain access I am located on port 8 which is the network and the dsl line is on ether 1 with address on rb and dsl modem ip is I did have access when directly plugged into it. As you can see I'm using to gateways with a very simple failover method which isn't working because when the dsl line fails it takes about 30 seconds to cause the ping to to fail and cause it to switch. Then the ping will come back within seconds and switch back to the dsl even if its not fully functional. Any help on this would be greatly appreciated. Thanks

Re: dsl problems need advice

Posted: Thu Jun 14, 2007 6:46 am
by illiniwireless
My failover problem is that I'm pinging the next device to make a decision on whether to switch gateways. How can I ping another address to make this decision. thanks

Re: dsl problems need advice

Posted: Thu Jun 14, 2007 4:33 pm
by galaxynet
illiniwireless -

Failover - there are a few scripts running around on the forum that can 'fix' what you are trying to do. There are two parts to doing it right though.

Part one is getting the script and adapting it to your system (putting in the correct IP addresses and such).

Part two is to use the route rule table. You'll have to know what IP address is the next one upstream from the MT through whatever device, i.e. your dsl modem - what is on the other end past the wan ip address of the dsl modem - in other words the dsl modem gateway....

Once you have these two pieces you can write a route rule that basically says - If the src address is such and the dst address is such-and-such then lookup table so-and-so. Table so-and-so would give a route to route that specific packet to, interface and gateway. When that IP doesn't respond (and you can set the time in the script) then the route would be down and the script will re-write the default gateway to your alternate. The script will also continue to run and when your dsl came back on line then the script would then re-write the default route again to your dsl line....

As to your other problem....

Your dsl modem probably does not know where to route packets from your network it sends the reply to whatever it's default gateway is.... Your best bet here is to src-nat your going to with an IP that the dsl modem would recognize as being local - something in the 192.168.1.xx range I would imagine...

If you cannot find that failover script - let me know - I have a generic copy around here somewhere.....


Re: dsl problems need advice

Posted: Fri Jun 15, 2007 6:35 am
by illiniwireless
Thank you very much for the info. I will see how far I can get on this and then let you know if I need more help.

Thanks again

Re: dsl problems need advice

Posted: Sat Jun 16, 2007 9:10 pm
by galaxynet
lliniwireless -
So - how did it go? Did you find the 'missing link' is your setup?


Re: dsl problems need advice

Posted: Mon Jun 18, 2007 7:54 am
by illiniwireless
Sorry, I've been out of town for a few days. I will be working on this Monday and Tuesday.

Re: dsl problems need advice

Posted: Sun Jun 24, 2007 10:55 am
by illiniwireless
Just thought I'd let you know that I fixed my problem. I tried the improved netwatch but failed to make it work so I made my own changes to that script (which was my first) and got it to work.

Thanks for your info.