I am in need of some basic steps in adding 2 new 3750 switch to an existing VLAN network of Stackable switches. The Stackable switches are 5 (WS-C3750X-12S-S ) in numbers.
I have an idea of what to configure if i was handling a 2950 switch. But this is my first attempt on a 3750 switch and don't want to mess it up.
After connecting these 2 new switches to the existing stack, do they automatically learn their number in the stack before any configuration is done?
Secondly, where will the configuration be done from; is it from the Master switch or directly on the new switch?
Normally on a 2950 switch, you configure it as a client in the existing domain and then configure VTP on the linked Ports between the switches before actually adding them to the network. Does that same rule apply?
by default a new switch
out of the box has a switch number of 1. When they
are added to the stack, the master will assign the number
to the switch. This is automatic, but as I've witnessed
in working with these, if you add two switches as
you are wanting to do, it's possible depending on the
rev of hardware (ie processor), the time it takes for
a switch to initialize and announce itself to the stack
can be different. If you add to switches to a five
stack switch, it's possible for the 7th switch to
actually receive the switch number of 6 because it
comes up first. Maybe I'm just paranoid, but I
like to manually change the switch number
(by doing "switch 1 ren XX" here XX is your new
switch number.
After the new switches are brought into the
stack by the master switch, a few seconds to
a minute or two later, the master will shadowcopy
the configuration down to the new members of the stack.
As TomS mentioned, the configuration is taken care of
from the management IP, which the master switch of
the stack will answer to.
You can tell the master two ways, either from the
status light on the front of the switch, or by
doing a "sh sw detail".
If you choose to view from the front of the switch,
you can also push the status button until you have
the stack light lit. At this point each switch in
the stack will flash one of the LED status lights for
the 10/100/1000 (if applicable) ports. This light
port number will reflect the switches number.
Example, switch 1 will flash the Fa1/0/1 light,
switch 2 will flash the Fa1/0/2 LED and so on.
You'll also not that the LED's of your last two
SFP ports will also light. If you have a 48 porter
Gi1/0/3 and Gi1/0/4's lights will light up Green
or Amber. IF you have a 24 port you only have
2 SPF ports unless you have a 3750G model.
These lights tell you the status of your Stackwise
cables and your 32Gig ring. If the ring is intact
both green lights will be on. If there is an issue
with the stackwise cables, one or both of the lights
will be amber. The amber lights show which switches
have issues. The stackwise cables can be touch at times.
If you use the "sh sw detail" you'll get an output like
this;
nocsw064#sh sw
Current
Switch# Role Mac Address Priority State
--------------------------------------------------------
1 Member 0017.941d.a780 15 Ready
*2 Master 0014.698c.af00 10 Ready
3 Member 0011.9307.c480 1 Ready
4 Member 0011.930f.8d80 1 Ready
5 Member 0011.930f.7880 1 Ready
6 Member 0011.930f.9a00 1 Ready
Stack Port Status Neighbors
Switch# Port 1 Port 2 Port 1 Port 2
--------------------------------------------------------
1 Ok Ok 2 3
2 Ok Ok 1 4
3 Ok Ok 5 1
4 Ok Ok 6 2
5 Ok Ok 3 6
6 Ok Ok 5 4
this shows many things, 1) how many switches
are part of the stack and their stack numbers,
2) who is master of the stack, 3) the priority
settings of each switch in the stack.
If you notice in the above, switch 1 has a priority
of 15 with when the stack is coming up, basically forces
switch 1 to be the master. Switch 2 has a priority of
10, which means if something happens to the master
switch 2 will take over the role of stack master.
If you notice there is a '*' next to switch 2's number.
This means it's currently the stack master, since
we had a issue with the master.
If you don't hard code the priority, any switch
in the stack can take over for the master. This
is decided in a election process similar to how a
master browser in windows is elected. UPtime, IOS
rev, MAC address and a few other factors come into
play. Instead of letting this happen we prefer to
hard code.
With the "sh sw detail" you'll see the second
part of the output shows the status of the stackwise
ports as well.
Also one more thing I remember, but didn't mention
earlier. If you're going to use etherchannel to
bundle Fa or Gi ports, this will act the same as
it does on the other switches, with the exception
in the case where you want to bundle ports between
ports of one or two other switches, you'll have to
mess with the WS-C3750V2-48PS-S PAg protocol, but it is possible.
