Sunday, 1 October 2017
Arista EOS - CLI quickstart
This is just a brain dump for me as I seem to very occassionally have to work on Arista switches - which by the way are pretty nice - mini version of linux on them.
Why do I like Arista - Andy Bechtolsheim (one of the founders of Sun Microsystems who I used to work for) - nice to have a mad scientist doing well ;-) - also good for Cisco to have some competition - monopolies are never a good thing. Also provided first (that I'm aware) of ULL switches. Other reasons I like it - it has linux (and so bash), sysdb - database on the switch that holds important data - used similarly to IPC, MLAG - allows port channels to exist on multiple switches at the same time, VARP - allows multiple switches to respond to arp requests for same IP, ZTP (zero touch provisioning) - loads config from network, LANZ - latency analyser, email, job scheduler (is this just cron?), tcpdump, event handlers, event monitors.
what version are we running:
what interfaces are attached and whats their status:
show int status
show interfaces ethernet 1-5 status
show run? (detail config with defaults)
what have I been doing here ;-) :
lets go crazy and make changes outside of change control and config management:
chicmsw01(config)#interface ethernet 8
Enter TEXT message. Type 'EOF' on its own line to end.
bash - gets us into a bash shell - nice if your from a linux background
bash python - wow!
environment -> can change fan speed etc
show logging ?
show log last 5 min
can configure syslog/email
show reload cause full (see why switch rebooted?)
lets ensure my crazy changes persist after a restart:
copy running-config startup-config
Also worked with implementing rancid - also pretty cool - dumps configs, saves to change control - and alerts me on any diffs.
Bash best practices A few hints on bash best practice: * use #!/usr/bin/env bash .. this is more portable but you cant rely on a spe...