Configuring Optimized Allocation of EVPN Host Routes 

Starting from NetVisor OS release 7.0.0 it is possible to leverage the host route hardware table to allocate IPv4 /32 and IPv6 /128 routes when advertised by EVPN. This is advantageous as the host route table provides ample additional allocation space (its size depends on the specific ASIC used by the switch).

To enable/disable the allocation in the host route table, you can use the following command: 

CLI (network-admin@switch) > system-settings-modify no-l3-use-host-table | l3-use-host-table 

The functionality is disabled by default. When it gets enabled, a switch reboot is requested with the following output message:  

"!!!! Please reboot the system for the new 

l3-use-host-table setting to take effect correctly !!!!"

You can verify the current configuration with this command: 

CLI (network-admin@switch) > system-settings-show format l3-use-host-table

l3-use-host-table: on

After being enabled and the switch being rebooted, a /32 IPv4 route or a /128 IPv6 route advertised by EVPN will get installed into the host table, for example as shown below:

CLI (network-admin@switch) > vrouter-evpn-bgp-routes-show | grep 2001 

vrouter-name rd        vni    mac               ip              route-type next-hop path extended-community                                  

------------ --------- ------ ----------------- --------------- ---------- -------- ---- ---------------------------------------------------- 

vr3 1005   00:12:c0:80:1b:e7 2001:20::10/128 2 101  RT:101:1005 RT:101:10020 ET:8 Rmac:66:0e:94:68:86:c2 

CLI (network-admin@switch) > vrouter-fib-arps-show | grep 2001 

vrid ip          if-id ports vnet bd vlan mac               egress-id flags   

---- ----------- ----- ----- ---- -- ---- ----------------- --------- --------

0    2001:20::10 2     22            1005 66:0e:94:68:86:c2 100061    Trunk