Injinj To be or not to be eventually consistent

Sonic Multipath

I upgraded my Arista 7050qx-32 SONiC to sonic-aboot-broadcom build #333 and installed SONiC on another Arista switch, the 7050qx-32s. The install on the 7050qx-32s was not successful initially, because my USB install device mapped to /dev/sda and the internal eUSB mapped to /dev/sdb, causing SONiC to try to install to the USB stick. Instead determining how to install to the right device, I used build #280 which worked, then upgrade the switch to #333 using ‘sonic_installer install sonic-aboot-broadcom.swi’.

The VLAN configuration that I had from build #280 no longer works in #333 on the 7050qx-32, not sure what is going on there. Also, the installed configuration for the 7050qx-32s had incorrect port mappings, so none of the ports initialized.

After fixing up the configuration so that each switch uses unique BGP ASNs and IP address ranges, I connected each of my hosts to both switches and published routes for the same local bridge to each BGP instance, causing multiple paths to be available. This diagram is how my lab looks now.

The Sonic configurations for this are config 7050qx32 and config 7050qx32s. The latter switch is routing through to the internet, so it is not currently publishing a route for the 10.0.1.0/24 network since the default route goes through it, but the first switch is publishing a route for the 10.0.0.0/24 network by declaring the BGP neighbor ports as part of the VLAN10 network. I’ll fix the second switch to publish it’s 10.0.1.0/24 route, but first I need to determine what needs to be done to configure VLANs in a Layer 2 network. Build #333 is not generating bridges for the VLANs declared in the config to /etc/network/interfaces, which is what it used to do in build #280.