trunk.md (2396B)
1 ### Trunk failover setup on OpenBSD 2 3 I have a dedicated machine at home that I use mainly for sending and 4 receiving e-mails. The machine has one wired interface as well as a 5 wireless interface. My wired interface goes over a powerline adapter. 6 For various reasons every once in a while, the powerline adapter loses 7 sync and as a result I cannot access my machine remotely. 8 One way to solve this problem is to take advantage of the wireless interface 9 and transparently switch over to it whenever the wired interface becomes unavailable. 10 To do this we'll use a simple form of interface aggregation, also known as 11 trunk failover. For the gory details please refer to: 12 13 # man 4 trunk 14 15 #### Setting up the interfaces 16 17 /etc/hostname.alc0: 18 19 up 20 21 /etc/hostname.athn0: 22 23 nwid <ESSID> 24 wpakey <your-key> 25 chan <your-channel> 26 up 27 28 /etc/hostname.trunk0: 29 30 trunkproto failover 31 trunkport alc0 32 trunkport athn0 33 inet 192.168.1.2 255.255.255.0 NONE media 100baseTX mediaopt full-duplex 34 35 Setting up the wired and wireless interfaces is straightforward and not 36 particularly interesting. 37 Our trunk setup is using the failover mode and is specified via `trunkproto`. 38 We have two allocated ports, the master port is hooked up to the wired interface 39 and the failover port is attached to the wireless interface. 40 In my setup I use a static IP address for the trunk interface but it is also 41 possible to use DHCP. 42 43 At this point restart the interfaces: 44 45 # sh /etc/netstart 46 47 #### Testing the trunk interface 48 49 Generate some network activity by copying a large file via scp and pull the 50 ethernet cable from your machine. The copy operation might stall but it will automatically 51 switch over to the wireless interface. If you plug your ethernet cable back in 52 it will switch to the wired interface. 53 54 A sample ifconfig follows from my particular setup: 55 56 trunk0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500 57 lladdr 90:e6:ba:74:0e:38 58 priority: 0 59 trunk: trunkproto failover 60 trunkport athn0 61 trunkport alc0 master,active 62 groups: trunk egress 63 media: Ethernet autoselect 64 status: active 65 inet 192.168.1.2 netmask 0xffffff00 broadcast 192.168.1.255 66 inet6 fe80::92e6:baff:fe74:e38%trunk0 prefixlen 64 scopeid 0x5 67 68 That's all :) 69 70 Cheers! 71 72 sin@