Nexus9K : scaling for VCP + HSRP/VRRP

[pascalfr0]

I've got a question about Nexus9K (9300),  VCP and HSRP/VRRP limits/scaling.

I'm thinking about a configuration with 2 Nexus9K running as L3 core, and some other Nexus 9K running as L2 access switches.

The 2 core swicthes will peer with L2 access switches using VCP links : the L2 access switches will see those links as classic LACP aggregated interfaces .

Using HSRP or VRRP, the core switches will be the default gateway for each VLAN extended towards the access switches.

I understand that in a VCP configuration, each member of the core will treat the trafic targeting the mac adress of the HSRP/VRRP gateway (kind of a active/active HSRP configuration used in VCP topology).

I have 2 questions :

- in such a configuration do we have the choice between VRRPv3 and HSRP or is HSRP mandatory ?

- the nx9k verified scaling guide gives a maximum number of 250 HSRP instances for the whole swith in case of Nexus9300. The same guide gives a maximum of 490 vrrpv3 instances. It seems kind low... especially if HSRP is mandatory (?) for VCP configurations. Do I miss something ?

thanks for your support,

Pascal

[Reza Sharifi]

You can use HSRP ver 2. It works really well when you want to match the HSRP ids with your vlan ids, e.g vlan 2000/HSRP group 2000.  HSRP ver 2 support up to 4096 groups (0-4095).

http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/5_x/nx-os/unicast/configuration/guide/l3_cli_nxos/l3_hsrp.html

HTH

[pascalfr0]

Interesting, thank you.

When I looked at Cisco verified scalability guide for nexus9300, i found this table :

Feature	9500 Series Verified Limit	9300 Series Verified Limit
Unicast Routing
BFD sessions (echo mode)	512	256
BGP neighbors	2000	512
EIGRP routes	20,000	20,000
EIGRP neighbors	512	256
HSRP groups	490	490
IPv4 ARP	48,000	48,000

VRRPv3 groups with relaxed timers (3 s)

490

490

So Cisco seems to offer 4000 HSRP group in HSRPv2, but would support only 490 groups based on verified designs / internal testing ?

[Reza Sharifi]

Not sure about this data. I know, I have deployed this in production with over 100 vlans. It works well and make management easier. Nice to know whatever the vlan id is, the same number is your HSRP group.

HTH

[EDOARDO A.]

Hi ,

in that kind of scenario if for example i have to configure 10 HSRP groups .. do you plane to share groups half and half on nexus? Or You configure the priority to the same device so they are all active on the same device.

TIA