RT-N66U Dual Wan configure one LAN IP to use just one ISP not either

[gphillips1965]

I have setup my router to to be dual wan with a cabled IP on the main wan and sky adsl through a LAN port

This works well and the LAN clients either router traffic out through the main ISP or the second ADSL modem connected to the RT-N66U


RT-N66U setup

WAN fixed IP x.x.x.x.x
LAN 192.168.1.1 255.255.255.0
DHCP 192.168.1.2 to 192.168.1.100

ADSL Modem

WAN dynamic ip from sky
LAN 10.10.1.1 255.255.255.0
ASUS second WAN on 10.10.1.100

I want to direct all traffic from one ip 192.168.1.4 through the fixed IP and not the SKY modem

I have read loads on this but can only find how to do it if i know the destination IP, i want all traffic to all IP's from 192.168.1.4 to go through the fixed IP

Thanks in advance for any help

 

[Martineau]

I have setup my router to to be dual wan with a cabled IP on the main wan and sky adsl through a LAN port

This works well and the LAN clients either router traffic out through the main ISP or the second ADSL modem connected to the RT-N66U


RT-N66U setup

WAN fixed IP x.x.x.x.x
LAN 192.168.1.1 255.255.255.0
DHCP 192.168.1.2 to 192.168.1.100

ADSL Modem

WAN dynamic ip from sky
LAN 10.10.1.1 255.255.255.0
ASUS second WAN on 10.10.1.100

I want to direct all traffic from one ip 192.168.1.4 through the fixed IP and not the SKY modem

I have read loads on this but can only find how to do it if i know the destination IP, i want all traffic to all IP's from 192.168.1.4 to go through the fixed IP

Thanks in advance for any help

In theory (I could be wrong!) a couple of additional commands in the appropriate sequence should achieve your goal:

ip rule add fwmark $TAG_MARK table $ISP_TABLE

iptables -t mangle -A PREROUTING -i br0 -m iprange --src-range 192.168.1.4 -j MARK --set-mark $TAG_MARK

the question is which routing table is being used by the ISP (WAN) and which routing table is being used by SKY

If you can already figure it out then simply use the two commands above with appropriate values for $TAG_MARK and $ISP_TABLE, otherwise

Issue

ip   rule

then if there are any tables besides 'main' and 'default' then I believe (can't set up DUAL WAN here at the moment) you can verify which one shows the ISP's WAN interface issue

ip   route   show   table   nnn

e.g. if table 101 is showing the route for the WAN ISP then the $TAG_MARK and $ISP_TABLE variables should be replaced by say '1' and '101' respectively.

Regards,

 

[gphillips1965]

i have done this and it seems to be working, thanks very much, do you need to add this every time you boot the router or is it saved

As an IT sales consultant i understand this stuff just not how to do it, i leave that to the smart people we just sell the dream

 

[Martineau]

i have done this and it seems to be working, thanks very much, do you need to add this every time you boot the router or is it saved

As an IT sales consultant i understand this stuff just not how to do it, i leave that to the smart people we just sell the dream

Unfortunately, as an IT Subject Matter Expert I have 'lived' the nightmares that have been sold by sales 'consultants' as we try to make them actually work in the real world!

The rules will need to be saved in say /jffs/scripts/wan-start and will need logic to determine if wan-start should issue these commands...i.e. for a DUAL WAN setup, wan-start is executed twice with the actual interface being supplied as a argument.

Clearly you cannot guarantee the order in which the ISP interface or SKY interface is initialised, although chances are the cabled ISP may always be UP first.

It probably wouldn't be the end of the world if the commands were issued every time an interface came UP...you would simply have redundant duplicate entries in the two tables.

Also if the ISP interface never comes UP, is it still appropriate that 192.168.1.4 has effectively no Internet outbound access?...in which case you may need to send an alert (email via SKY?) to your phone to let you know there is an issue,

Regards,