Static ARP entry using ip arp-mcast-replies

[Jerome Covini]

How can I create a static ARP entry on a Procurve Switch like the 5412/8212 ?

What is the command, I can't find it ?!

P.S. This thread has been moved from Switches, Hubs, Modems (Legacy ITRC forum) to ProCurve / ProVision-Based. - Hp Forum Moderator

[Case Van Horsen]

To associate a MAC address with a port, use the "port-security" command.

To associate an IP address and MAC address, use the "ip source-binding" command.

casevh

[Mohieddin Kharnoub]

Hi

I think DHCP Snooping must be enabled to have this binding between ARP and MAC result from :
ip source-binding

Good Luck !!!

[Jerome Covini]

>To associate an IP address and MAC address, >use the "ip source-binding" command.

That's for the DHCP snooping database isn't it ?!?!

I need to create a static ARP entry in the ARP table, not in the DHCP snooping database. I am not using DHCP snooping.

[Matt Hobbs]

Static ARP is not an option on these switches. You can increase the ARP age and mac-age timers but that's about it.

Why exactly do you need to create a static ARP entry? Maybe there is some other solution?

[Jerome Covini]

Hi Matt,

I need it for MS NLB Multicast.

[Matt Hobbs]

Without the static ARP entry, does it work at all? I just want to confirm if it does not work, or if you're trying to limit the flooding due to the multicast-mac not being installed in the ARP table.

[Jerome Covini]

The problem is not the L2 flooding.
What does a router when it receives packet for a directly connected subnet, and if the target host is not found into ARP table ? It ARPs for it.
Problem, ARP protocol is not designed to deal with multicast macs, only unicast mac. By essence, multicast uses GARP / GMRP instead.

RFC 1812 : "... A router MUST not believe any ARP reply that claims that the Link Layer address of another host or router is a broadcast or multicast address...". That's what the procurve will purposedly do, hence the need for a static ARP entry when using NLB Multicast.

[Matt Hobbs]

I think you're out of luck for the time being and you'll probably have to use Unicast mode or a different router. It seems like Static ARP would be a feature we'd have seen by now. I would recommend you contact your ProCurve sales rep to see if they can push for this feature to be added.

[Ian Witts]

We have encountered the exact same problem; that this enterprise-level switch doesnt allow you to add a static ARP Entry.

It's just not good enough.

That's the last time we use a HP switch (it's now caused us all sorts of problems regarding our customer requiring MS NLB to load balance their web servers).

Not happy at all.

WittZi.

[Chris991]

I need also a static ARP entry for MS-NLB on a ProCurve 5400. Is static ARP in the newest Software revision implement?

[Antonio Milanese]

Hi Jerome,

on latest OS images K15.02.xx or K.14.55.xx and above:

ip arp-mcast-replies

You cannot create a static arp entry like on cisco gears but the switch will handle the mcast mac address as ip multicast.

*Note*: we are *still* talking about per RFC1112 (01:00:xx..)mcast addresses and not Microsoft "creative" ones (03:BF:xx..) and so yes you have to use NLB/IGMP mode.

Regards,

Antonio

[Mauro Furini]

And for Microsoft "creative" version?
Anyone has experience with ex 3Com-H3C?

[Antonio Milanese]

Hi Mauro,

as Matt say you are out of luck because the switch will not save an ARP entry since you have a multicast MAC (03:BF:xx) BUT an unicast IP (cluster VIP).

H3C gears have static MAC/ARP support in unicast and musticast mode.
We plan to use H3C hardware on some customers when they will upgrade core facility since are more competitive on cisco (well sort of=) "datacenter" advanced features (IRF to name one..and no i dont like procurve DLACP limitations).

Regards,

Antonio

[Manfri]

i confirm that on a 5400 zl the ip arp-mcast-replies works for K.15.02.0005 and i wold like to thank everyone: you have just saves my week ( maybe month )

[Ivan-Aust]

i also confirm K15.03.0007 adds the ip arp-mcast-replies to the 8212zl switch.

Using WNLB you must enable IGMP on the switch and configure the NLB cluster in Muiticast with IGPM.

Wait for the ARP table to update - depends on the aging set on your switch and all is good.

[Siva_HP]

Hi All,

I need one clarification on same topic. Here we have Procurve 8212 core switch, Procurve 6600 as Distribution Switches and Procurve 5412 access swtiches. My servers are connected to Procurve 5412. Please let me know one which switch I need to apply the below command to enable the NLB.

ProCurve(config)# ip arp-mcast-replies

Regads,

Siva

[Scott Seifel]

I too need to possibly add a static ARP on a 3500yl switch with the Premium license.  Can someone explain to me how ip arp-mcast-replies works and if it is a substitution for adding a static ARP entry when used with IGMP and Microsoft NLB multicasting - IGMP mode.

Thanks.

[Alfredo_dpcdsb]

Anyone know what the arp entry limit is on a 3500yl?