Dell PowerEdge w/ Intel AFT / Broadcom BASP

Brian A. Seklecki lavalamp at
Wed Oct 5 11:15:30 PDT 2005


This may be better for freebsd-cluster at, but that list is kind 
of ghost town, and this question is more a standards-based:

Does anyone deploy Dell Poweredge in a HA configuration utilizing these 

Do we know what underlying standards and protocols compose these 
"technologies"? 802.3ad, Cisco FEC?

Intel AFT claims to provide redundancy over a "team" of NICs.  ALB claims 
link aggregation; but they don't specify if they're doing it in hardware 
or sofware (see Below)

Broadcom BASP claims the same, given different terminology and vendor.

I'm looking for a "fault tolerant" configuration for a HA cluster.  "Load 
balancing" and/or "link aggregation" is not required.  I need to be able 
to "team" two NICs into one Virtual NIC.  Each NIC connects to two 
redundant managed switches, on which the connecting switch ports exist in 
the same VLAN (which is then ISL/802.1q trunked between them).  Essentially
the same ethernet segment.

I see ng_one2many(4), but the man page doesn't really state what standard 
that uses.  It seems to be all in-kernel magic (LACP and aren't 
mentioned in the man page); will this meet the above requirements?

There were some ng_one2many(4) patches a while back to add more 
intellegence, (FEC/802.3ad heartbeat like control protocol)
...but no mention of them ever being commited.

I see ng_fec(4) also, but I don't think that Cisco Ethernet Channel can 
occur between two switches and one server (correct me if I'm wrong).

I question the Hardware v.s. Software issue on the Intel NICs becase the 
Dell PowerEdges Severs that happen to have Intel NIC Chipsets using em(4) 
(many have Broadcom), seem to automatically try to "team" NICs when 
they're connected to unmanaged PowerConnect switches, breaking ng_one2many 
logic.  They constantly alternate MAC addresses between the primary 
ethernet, the secondary ethernet, and a 3rd 1-byte-off Virtual MAC.

This automatic attempt to team seems like a hardware feature.  If it was a 
software feature, in theory it wouldn't try to team w/o being instructed 

On the other hand, *managed* Dell PowerConnect switches feature something 
called "LAG", which the docs describe as 802.3ad / LACP.

I haven't tried ng_one2many on non-Dell or Dell Managed switches to see if 
the MAC address "bouncing" problem persists, but I'll try that today.

So the big question:

  *) Is the Windows/Linux-only software for configuring "teams" of NICs,
     described in the URLs below, designed to configure a hardware level
     feature that might have more intellegent link failure detection than
     ng_many2one? (I.e., other than just lost carrier, say, STP storm
     detection or excessive packet error thresholds).  Or is it software?

  *) If it is a hardware feature, could our em(4) driver be adapted or
     could it possibly be configured using OpenManage via the Intel
     IPMI/DMI/SMI whatever?

  *) Can Cisco FEC or 802.3ad provide reundancy between two switches and
     one server w/ two NICs?  Will NetGraph ever have a 802.3ad module?

  *) What combination of Switch and NIC related teaming / failover technology
     are known to be compatible with FreeBSD ?


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