[K12OSN] nfs troubles

[Les Mikesell]

Roger wrote:
> On Nov 16, 2007 12:08 PM, "Terrell Prudé Jr." <microman at cmosnetworks.com> wrote:
>>  Yep, I can see that happening.  Remember that, with IPX/SPX, the network
>> address is done by MAC address (not so with IPv4), and the addresses are
>> thus auto-assigned (no DHCP).  IPv6 "borrowed" this little trick and thus
>> doesn't need DHCP any more than IPX does.
> 
> yep remembered the addressing. this was 5 or 6 years ago, so I wasn't
> really sure what the problem was.  it did have something to do with no
> IP address.   I think what the user saw was getting a login to the
> file server, but their mail wouldn't work or something.  that's when
> we got to digging around and found out that pesky delay.   I think
> spanning tree has two or three 30 second delays during the port
> enabling process.   A listening phase, a learning phase, something
> else, then it enables the port.
> portfast essentially bypasses the listening and learning.  (dang, is
> that the name?)..  It just enables the port.    It does enable
> spanning tree, just the pre-enabling checks aren't done.

Portfast doesn't really stop the spanning tree process - it just 
forwards packets during this step.  It will still shut the port down if 
it learns it is a loop (unless there is so much traffic that it drops 
the packets it needs to see that...).  Just remember never to plug 
another switch into a port you have set to portfast mode and you won't 
have loops.

-- 
   Les Mikesell
     lesmikesell at gmail.com