[nanog] Cisco GLBP/HSRP question -- Has it ever been dis

Tue Aug 6 03:20:51 UTC 2019

On 8/5/19 1:17 PM, Vincentz Petzholtz wrote:
> And as far as I remember: If a member fails then another one is taking 
> over responsibility over the used mac address.

That's my understanding as well.

> It surprised me a little bit that this never really taken off (not 
> even within Cisco folks in the enterprise field as far as I know).

The few times that it's been discussed with colleagues has usually run 
into an issue of "how do we do GLBP between two L3 switches?".

I get the impression that GLBP would be more likely used with separate 
routers connected to common switches that didn't do L3 switching.

> I was also keen if/when this ever get available on other vendors 
> and/or open source software.

Agreed.

I did some sleuthing and just learned that OpenBSD's Common Address 
Redundancy Protocol (also ported to other *BSDs and Linux) does support 
an active/active configuration.

I found some details in FreeBSD's carp(4) man page.  Search said page 
for "net.inet.carp.arpbalance".

So … I'm going to need to do some pontification about CARP.  }:-)

> Just as everybody else we do run two VRRP instances with ECMP style 
> routes on datacenter gear a lot.

I see VRRP used a lot as a way to move VIPs between servers for similar 
redundancy reasons.

> But in some situations it would be nice to have something to spread 
> the traffic across different routers (even when the client is too 
> „dump“ for ecmp routes).

Yep.  Cisco's GLBP can do that.  I now know that OpenBSD's CARP can do 
that too.  (#todayilearned)

-- 
Grant. . . .
unix || die

-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4008 bytes
Desc: S/MIME Cryptographic Signature
URL: <http://mailman.nanog.org/pipermail/nanog/attachments/20190805/a7491669/attachment.bin>