S1E3 - Introduction to the Arista CLI
S1E3 - Introduction to the Arista CLI
(and a bit about how it works with containerlab and docker)
Tech Stack overview
- VM in the Hetzner Cloud (named “netlab.nanocat.net”)
- .. running Linux (Debian 11)
- .. and docker
- .. and containerlab
- containerlab creates containers based on a YAML file
- and runs EOS images (called cEOS) that I downloaded from Arista.com
- (and also tiny Linux images, to act as “PCs” in the LAB)
Connecting to the lab server
Connect to the lab server:
local$ ssh-keygen -R netlab.nanocat.net
local$ ssh lab@netlab.nanocat.net
Password: (see discord)
Connect to your router:
lab@netlab$ list-devices
lab@netlab$ connect DEVICE
enable and disable modes
You will almost always enter enable
as your first command after
logging into your EOS (or IOS) device.
enable (privileged) mode
router>enable
router#
prompt#
- changes to the configuration possible
- more access to detailed
show
commands
disable (unprivileged) modes
router#disable
router>
prompt>
- no configuration changes possible
- safe, even for public access (search the web for “bgp looking glass telnet”)
?
and <TAB>
-
?
and<TAB>
are used for help and command completion respectively. Try entering these commands:show ?
show ip ?
show ip route ?
sh<TAB> ip ro<TAB>
-
Commands can be abbreviated to their shortest unambiguous length. Try these:
show running-config
show running
show run
sh run
sh ru
The show
command
Show commands tell us about the device hardware status, its protocols, software version, and so on.
Try these commands:
show version
show running-config
show interface
show interface status
show ip interface
show ip interface brief
Changing the Configuration
Entering “Global Configuration Mode”:
router#configure
router(config)#
Configuring an interface:
router(config)#interface ethernet1
router(config-if-eth1)#description This interface connects to the switch
router(config-if-eth1)#
Exiting interface configuration, back to global config, then exit config mode:
router(config-if-eth1)#exit
router(config)#exit
router#
Look at the configuration:
router#show running-config
Configuring an interface
Configuring an IP address on an ethernet interface:
router#configure
router(config)#interface ethernet1
router(config-if)#ip address 172.17.0.1/24
! IP configuration will be ignored while interface Ethernet1 is not a routed port.
router(config-if)#no switchport
router(config-if)#exit
router(config)#exit
router#show ip interface brief
...
Reconfiguring an interface
Changing an IP address on an ethernet interface:
router#configure
router(config)#interface ethernet1
router(config-if-eth1)#ip address 10.0.0.1/24
router(config-if-eth1)#end
router#show ip interface brief
...
Reconfiguring an interface, again
Removing the IP address from an ethernet interface:
router#configure
router(config)#interface ethernet1
router(config-if-eth1)#no ip address
router(config-if-eth1)#end
router#show ip int brief
...
Discovering our neighbours
Checking our LLDP neighbours:
router#show lldp neighbor
...
Ping another device:
router#ping 10.0.0.4
...