[RndTbl] Small switch recommendation.

Adam Thompson athompso at athompso.net
Fri Jun 2 06:32:20 CDT 2017

> > ones) where MAC address per-port assignment was horribly broken
> (same
> > MAC applied to all ports in MGMT & SNMP interfaces).
> Sounds like a one-off problem, doubt that's the case on all their switch
> lines.

Nah.  Quite a few switches do that.  "It's a feature, not a bug."  Seriously.  Actually, it's an artifact of the way the switch silicon is designed; pretty much the only switches that *don't* do this are from Cisco or Juniper or someone else who designs their own switch silicon, because it's a design feature of all the standard switch silicon vendors.
It's also not unique to switches - consider that Sun also thinks "it's a feature, not a bug" - all SPARC systems use one global MAC address across all interfaces by default.
And even from a theoretical standpoint, the switch mgmt. interface is usually just a VLAN'd interface (embedded in silicon, talking directly to a special internal switchport) and last time I checked, when I instantiate VLAN subinterfaces on Windows, Linux, OpenBSD, FreeBSD, etc. the subinterfaces get the same MAC address as the parent interface.
IMHO, Cisco is the outlier here.

Unless I'm misunderstanding Sean's original complaint?

> > I may end up just going fully managed (for device location hunting)
> > but could use some product suggestions from the above described
> > scenario.
> Looks like only fully-managed (CLI) switches can do the advanced stuff
> you need.  Funny that the stumbling block is the mirror thing.

That's not surprising.  The CLI-enabled switches are using the higher-end OEM silicon.  So Broadcom (or one of their competitors) had to go up a die size to get enough CPU & RAM to handle three interfaces (Web, CLI, settable SNMP) and a couple more daemons (telnetd, sshd), they likely had enough extra gate capacity to bump up the feature set a little bit on every feature.
The OEMs provide a single "column" of switch chips where you as a switch-maker get to pick from XS, Small, Medium, Large, XL, 2XL, etc., not a full feature-matrix.


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