topic RE: netscaler/citrix server send gratuitous arp which is not recordnised by S8 Core Switch in ExtremeSwitching (EOS)

netscaler/citrix server send gratuitous arp which is not recordnised by S8 Core Switch

Nico_Lueck — Tue, 02 May 2017 15:44:00 GMT

Our Customer is using a netscaler. Server (main&backup) is using same IP Address.

When there is an failover on server site, the server sends a gartuitous arp message.
The core switch (S8) does not recordnise this massage, so it too the default value of apr/mac timeout of 300sec the S8 will recordnise the MAC of the server which is now activ after failover.

is there any chance to get the gartuitous arp message tracked by the core without changing the arp/mac timeout?

many thanks!

RE: netscaler/citrix server send gratuitous arp which is not recordnised by S8 Core Switch

Bastian_Sprotte — Tue, 02 May 2017 16:15:00 GMT

hello,
did you test with enabled gratuitous-arp-learning.

interface vlan.0.1010
ip address 192.168.10.2 255.255.255.0 primary
ip gratuitous-arp-learning both
no shutdown
exit

S8(su-config-intf-vlan.0.1010)->ip gratuitous-arp?
gratuitous-arp Enable updating existing arp binding from gratuitous-arp
gratuitous-arp-learning Enable learning new arp binding from gratuitous-arp

regards
Bastian
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RE: netscaler/citrix server send gratuitous arp which is not recordnised by S8 Core Switch

Nico_Lueck — Tue, 02 May 2017 18:32:00 GMT

Hi Bastian,

does that have an impact on traffic/cpu performance?

Thanks
Regards
Nico

RE: netscaler/citrix server send gratuitous arp which is not recordnised by S8 Core Switch

Bastian_Sprotte — Tue, 02 May 2017 18:40:00 GMT

no impact, just processing the gratuitous-arp packets and update the IP/MAC info as requested.
Bastian
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RE: netscaler/citrix server send gratuitous arp which is not recordnised by S8 Core Switch

Nico_Lueck — Tue, 02 May 2017 18:42:00 GMT

Thanks a lot for your quick help here!