Open Infrastructure

h1. How to configure Arista switches

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h2. Saving your changes

If you don't enter write at the end, everything is lost after reboot.

<pre>

write

</pre>

h2. Entering conf mode

<pre>

enable

conf

</pre>

h2. Setting password

<pre>

username admin secret <passwordhere>

</pre>

h2. Setting name

<pre>

hostname <NAME>

</pre>

By default set it to *switch-placeX*. While the placeX part is indeed redundant, it is necessary to be able to distinguish switch1.place5 and switch1.place6.

h2. Creating a VLAN

<pre>

vlan <ID-OF-VLAN>

name <NAME-OF-VLAN>

</pre>

h2. Putting a port into a untagged vlan

<pre>

interface EthernetXX

   switchport access vlan YY

</pre>

h2. Creating a port channel (= LACP = bonding)

* go to the interface that you want to be in the port-channel

* configure it

<pre>

interface EthernetXX

   channel-group XX mode active

</pre>

h2. Creating a port channel over multiple switches using MLAG

<pre>

interface EthernetXX

   channel-group XX mode active

interface port-channel XX

   mlag XX

</pre>

And if you want to have tagged/trunk port:

<pre>

   switchport mode trunk 

</pre>

If you want to have untagged connections to be automatically tagged:

<pre>

switchport trunk native vlan <VLAN>

</pre>

If you want to allow fallback of lacp:

<pre>

port-channel lacp fallback static

port-channel lacp fallback timeout 20

</pre>

h2. Upgrading a switch

* copy the image from usb to flash

* change the boot config

* don't forget to write

* reload

<pre>

copy usb1:/EOS-4.14.4.swi flash:/EOS-4.14.4.swi

configure terminal

boot system flash:/EOS-4.14.4.swi

show boot-config

write

reload

</pre>

h2. Configuring MLAG

* Create a port channel for communication

* Configure the mlag over it

* Assuming the switches are connected by ethernet 47 and ethernet 48

* Assuming that the switches use vlan 13

* ZZ = ip suffix of the switch

* WW = ip suffix of the other switch

* mlagdomain = something local

<pre>

interface ethernet 47

    channel-group 47 mode active

interface ethernet 48

    channel-group 47 mode active

interface Port-Channel47

   switchport mode trunk

   switchport trunk group mlag-aristas

vlan 13

   name mlag-aristas

   trunk group mlag-aristas

interface Vlan13

   no autostate

   ip address 10.3.4.ZZ/24

mlag configuration

   domain-id MLAGLOCALDOMAIN

   peer-address 10.3.4.WW

   local-interface Vlan13

   peer-link Port-Channel47

</pre>

h2. Combining (MLAG+nolacp) + (Trunk+untagged vlan fallback)

* Allow servers to netboot

* Without LACP active

* Without VLAN tagging active

Configuration valid for both switches:

<pre>

interface Port-Channel1

   switchport trunk native vlan 10

   switchport mode trunk

   port-channel lacp fallback static

   port-channel lacp fallback timeout 20

   mlag 1

!

interface Ethernet1

   channel-group 1 mode active

</pre>

h2. Configuring BGP

* XX = ip suffix

<pre>

router bgp 209898

   router-id 0.0.0.XX

   bgp default ipv6-unicast

   maximum-paths 4

   bgp listen range 2a0a:e5c0:1:8::/64 peer-group ungleich remote-as 209898

   neighbor ungleich peer-group

   neighbor ungleich maximum-routes 12000 

</pre>