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On Saturday, 24 October 2020 05:55:54 BST Walter Dnes wrote: |
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> After an outage on VDSL last month, I got a backup 10/1 cable |
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> subscription backup. Switching is a bit of a hassle. In addition to |
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> swapping cables, I have to run dhcpcd as root or sudo when swithching |
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> from VDSL to cable. Switching back I have to run "dhcpcd -x", copy over |
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> my backup of /etc/resolve.conf, and run "/etc/init.d/net.eth0 restart". |
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> |
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> The VDSL router/modem offers dhcp and static address space at |
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> 192.168.1.0/24, DNS and default GW 192.168.1.1. I've bought a router |
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> that gets a WAN address from the cable modem via dhcpcd, and offers dhcp |
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> and static address space at 192.168.10.0/24, DNS and default GW |
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> 192.168.10.1. My current /etc/conf.d/net is... |
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> |
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> mtu_eth0="1466" |
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> config_eth0=" |
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> 192.168.1.249/24 broadcast 192.168.1.255" |
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> routes_eth0=" |
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> default via 192.168.1.1 metric 20 |
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> 192.168.1.240/28 via 192.168.1.1 metric 0" |
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> |
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> ...for my machine 192.168.1.249. Can I have something like... |
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> |
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> mtu_eth0="1466" |
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> config_eth0=" |
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> 192.168.1.249/24 broadcast 192.168.1.255 |
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> 192.168.10.249/24 broadcast 192.168.1.255" |
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> routes_eth0=" |
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> default via 192.168.1.1 metric 20 |
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> 192.168.1.240/28 via 192.168.1.1 metric 0" |
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> |
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> ... and how would I tweak the last two lines to work without changes |
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> each time I switch between VDSL (192.168.1.1) and cable (192.168.10.1) ? |
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|
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In file '/usr/share/doc/netifrc-0.7.1/net.example.bz2' examples are given to |
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set up interface gateways using arping. In your case I think something like |
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this ought to work: |
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|
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############### |
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mtu_eth0="1466" |
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|
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gateways_eth0="192.168.1.1 192.168.10.1" |
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|
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config_192168001001="192.168.1.249/24" |
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routes_192168001001="default via 192.168.1.1" |
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dns_servers_192168001001="192.168.1.1" |
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|
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config_192168010001="192.168.10.249/24" |
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routes_192168010001="default via 192.168.10.1" |
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dns_servers_192168010001="192.168.10.1" |
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############### |
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|
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If you physically plug and unplug the ethernet cable from the PC to either |
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router each time, the PC's IP address will be set statically according to the |
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router's LAN address. |
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|
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However, if only one router is connected to the PC at any time, my personal |
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preference would be to use the *same* LAN subnet on both routers and configure |
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the routers' static IP address allocation to the same IP address for the PC's |
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MAC. |
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|
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An alternative would be to have the PC connected to both routers over a |
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managed switch and then use a more involved configuration to monitor the VDSL |
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connection by pinging an Internet address, or the next hop to the ISP's |
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gateway, or their DNS servers. When multiple pings fail, the routing would be |
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switched over from VDSL to the Cable router. This would be a more convoluted |
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set up, probably using a post-up script to do the failover monitoring and re- |
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routing. I don't have a working netifrc setup to share, but professional |
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grade managed switches/routers should be able to do this if you don't want to |
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do it on the PC itself. |