HWIC-D-9ESW (was: Re: [c-nsp] spanning-tree problems)

[Reuben Farrelly]

On 10/12/2005 11:56 a.m., Suchy Daniel wrote:
> 
> Adam Greene wrote:
>> I'd have to do some investigating to determine whether it's all Rapid 
>> PVST,
>> but judging from the configs on the 3750, the switches were configured 
>> using
>> generic Cisco macros, so I wouldn't be surprised if they are all the 
>> same.
>>
>> I'm not too good at interpreting the debug output, but it looks to me 
>> like
>> spanning-tree is not converging rapidly, which makes me wonder what the
>> network topology actually is, and whether there are truly some redundant
>> links and potential loops I am needing to be aware of.
> 
> Etherswitch module (in 2801) supports only 802.1D = (legacy) STP - at 
> least is this reported in datasheet (I haven't real experience with this 
> box). Rapid STP is 802.1w. Benefits of fast convergence in segment with 
> RSTP are lost, when it interacts with device running (legacy) STP 
> device. It's also question, if etherswitch module supports/runs PVST, 
> standard STP is global for all VLANs, there's no per-VLAN STP instance 
> separation.

That actually brings up a good point that I was discussing with one of my 
co-workers yesterday.  We have a number of 2801s and for a customer have 
deployed the HWIC-D-9ESW, which is potentially quite a handy piece of hardware.

http://www.cisco.com/en/US/partner/products/ps6350/products_configuration_guide_chapter09186a00804554c7.html

What is most odd is the configuration of this card in IOS.  As Suchy said, it 
does not support Rapid PVST which means that your all cisco network can't 100% 
interoperate except by falling back to non rapid PVST on ports where non Rapid 
devices exist.  VLANS must be configured by going into the vlan database mode 
and the VLAN config doesn't show up in the config (in vlan.dat instead which 
must be backed up separately).  Also, on trunks you must specify vlans 
1,1002-1005 as being permitted else it complains about the mandatory but unused 
vlans being left out.
Much the same deal with the WIC-4ESW, although that one is admittedly a bit older.

What gives with this?  Did the guys who wrote the IOS code for this module grab 
the switching code from the switching groups dustbin about 4 years ago when that 
was current, thinking they'd found a bargain, and never care to update it to 
something more recent?  The vlan database method of configuring vlans was 
deprecated for switches long ago, so it's odd that it is now the _only_ way to 
configure a brand new bleeding edge piece of cisco kit.

More seriously though, one of the big plusses in buying cisco has always been 
the consistency and interoperability between platforms especially the ones 
running IOS.  This card has in my opinion been a step backwards in that regard. 
  It's still handy to have but it's not even as capable or useful as the lowest 
end Catalyst 2940 8 port switch (which I might add as a sidepoint, is a very 
nice piece of L2 switching gear at the edge).

Are there any plans or thoughts to address this in future versions of IOS?

reuben