topic Re: CES Gratuitous ARP in Data Center (MLX & CER/CES)

CES Gratuitous ARP

lcarl — Tue, 28 Apr 2020 05:40:02 GMT

Turning up an LTE link and wanted to know if the Extreme CES supported GARP. Apparently the LTE device was sending requests and causing Network issues. LTE TAC recommended to turn on GARP.

Re: CES Gratuitous ARP

Michael_Morey — Tue, 28 Apr 2020 20:10:34 GMT

I believe what you are wanting to do is setup VRRP-E on your CES device:

When a CES is configured for VRRP-E and becomes the master route, it broadcasts a gratuitous ARP (GARP) request containing the virtual router’s MAC address for each IP address associated with the virtual router.

The general steps to do so are as follows:

NetIron CES 2048CX#conf t
NetIron CES 2048CX(config)#router vrrp-extended
NetIron CES 2048CX(config-vrrpe-router)#int e 1/5
NetIron CES 2048CX(config-if-e1000-1/5)#ip address 10.53.5.3/24
NetIron CES 2048CX(config-if-e1000-1/5)#ip vrrp-e vrid 1
NetIron CES 2048CX(config-if-e1000-1/5-vrid-1)#backup priority 50 track 10
NetIron CES 2048CX(config-if-e1000-1/5-vrid-1)#ip-address 10.53.5.1
NetIron CES 2048CX(config-if-e1000-1/5-vrid-1)#virtual-mac aaaa.bbbb.cccc
NetIron CES 2048CX(config-if-e1000-1/5-vrid-1)#activate
NetIron CES 2048CX(config-if-e1000-1/5)#end

You can find out more regarding VRRP-E and GARP in the NetIron Routing Guide

Re: CES Gratuitous ARP

lcarl — Tue, 28 Apr 2020 21:05:39 GMT

I don’t believe implementing or planning to implement. Found other vendors that support and customer asks if CES supported. I will verify with the customer today

Ruckus documentation

Learning gratuitous ARP enables Ruckus Layer 3 devices to learn ARP entries from incoming gratuitous ARP packets from the hosts which are directly connected. This help achieve faster convergence for the hosts when they are ready to send traffic.

A new ARP entry is created when a gratuitous ARP packet is received. If the ARP is already existing, it will be updated with the new content.

To enable learning gratuitous ARP, enter the following command at the device configuration level.
device(config)#ip arp learn-gratuitous-arp

From Vendor B

Configuring Gratuitous ARP

By default, Arista switch interfaces reject gratuitous ARP request packets. The arp gratuitous accept

command configures an L3 interface to accept the gratuitous ARP request packets sent from a different

device in the network and add their mappings to the ARP table. Gratuitous ARP can be configured on

Ethernet interfaces, VLANs/SVI, or L3 port channels, but has no effect on L2 interfaces.

Example

• These commands enable gratuitous ARP packet acceptance on Ethernet interface 2/1.

switch (config)# interface ethernet 2/1

switch (config-if-Et2/1)#arp gratuitous accept

Re: CES Gratuitous ARP

Michael_Morey — Tue, 28 Apr 2020 23:05:57 GMT

I believe I better understand your question.

My initial response was regarding the generation of GARP packets via the VRRP interface.

I understand you are asking about the device accepting GARP packets.

By default NetIron devices accept GARP packets:

NetIron CES 2048CX#show ip int ve 12
Interface Ve 12
type: vlan
vlan-id: 12
members: none
active: none
port enabled
port state: DOWN
ip address: 10.10.10.1/24
Port belongs to VRF: default-vrf
encapsulation: ETHERNET, mtu: 1500
directed-broadcast-forwarding: disabled
ip icmp redirect: enabled
ip local proxy arp: disabled
ip ignore gratuitous arp: disabled
No inbound ip access-list is set
No outbound ip access-list is set
No Helper Addresses are configured.
RPF mode: None RPF Log: Disabled
0 unicast RPF drop

A device would have to be configured manually to ignore GARP:

NetIron CES 2048CX#conf t
NetIron CES 2048CX(config)#int ve 12
NetIron CES 2048CX(config-vif-12)#ip local-proxy-arp ignore-gratuitous-arp
NetIron CES 2048CX(config-vif-12)#show ip int ve 12
Interface Ve 12
type: vlan
vlan-id: 12
members: none
active: none
port enabled
port state: DOWN
ip address: 10.10.10.1/24
Port belongs to VRF: default-vrf
encapsulation: ETHERNET, mtu: 1500
directed-broadcast-forwarding: disabled
ip icmp redirect: enabled
ip local proxy arp: enabled
ip ignore gratuitous arp: enabled
No inbound ip access-list is set
No outbound ip access-list is set
No Helper Addresses are configured.
RPF mode: None RPF Log: Disabled
0 unicast RPF drop