Hello Folks
Question 1)
So I configed a pair of 4506e with VSS and it was working fine after verification and everything, and I even had this template of Gig Y/x/x on one switch which Y is the Switch number and the other switch was in standby mode that had no access to any commands, so I saved the config, turned off both of 'em
next day I assume I did nothing but disconnecting one of the cables in between the pair to use the cable somewhere else,
after I turned them on again, not only they are not seeing each other but
on the switch number 2 with lower priority which used to be a standby switch, I can't even type the command switch or show switch anymore,
what can I do other than erasing the nvram? I have no access to command switch anywhere which is funny, neither privilege nor config mode
Question 2)
What is the best practice of connecting a stackwised(Distribution level) switch to a VSS switch, connect to both VSS pairs or to just one of 'em? what's the common practice in productions?, I think it doesn't matter that VSS is a one logical switch, you can still get a better performance when you access them both directly, right?
thx a lot
Answer to my questions ;)
1) I still need some explanation for this.
2) No you don't need to config your switches to do stackwise(for the most part)
Today I will open the box of pandora of switch virtualization Switch virtualization is needed for configure etherchannels or LACP over two or more devices, configuration-redundancy, single-configuration and easy network expansion. In this example I will show you how to configure a stackwise cluster with Cisco Catalyst 3750-X switches:
with Cisco StackWise you can bound several standalone-switches to one core-switch (the backbone will be connected together with Stacking-Cables (0,5, 1 or 3 meters):
You can connect two devices with only one StackWise-Cable but for full bandwith and redundant connection, you need to connect the devices to a ring topology:
Before connecting two devices together, make sure that both devices have the same IOS software installed. The configuration of the StackWise Cluster is done automatically by connecting the stack cable. One switch will be the master within the cluster. The election is done as follow at connect or boot:
- Specified by user
- Switch with the highest IOS feature-set (Advanced Enterprise wins against Advanced IP Services)
- Uptime (longest running Switch wins)
- MAC Address (Switch with the lowest mac addresses will become master)
I recommend to configure the priority value of each switch so the configuration and the physical structure (top-down, A, B, C, etc.) keeps straight and didn’t confuse the administrator or someone who needs to troubleshoot the infrastructure OR you have differnet switch-models within one cluster. In our example Switch A is running for an hour and we connect another device (same device-model, same IOS software) to the main switch with a stacking cable. The second device “Switch B” will be select as Slave, because we didn’t configure anything and “Switch A” has a longer uptime. You will see that other interfaces are coming up and you can view all devices with this:
CoreSwitch# show switch
Current
Switch# Role Mac Address Priority State
--------------------------------------------------------
1 Master 0016.4748.ff12 5 Ready
2 Slave 0016.9d59.db00 1 ReadyThe stack member number is the same as can be seen in the interfaces:
interface GigabitEthernet1/0/1 = 1st Port of Switch with ID #1
interface GigabitEthernet2/0/1 = 1st Port of Switch with ID #2
You can define the priority of each switch. The higher the priority, the lower the switch stack-member-number. For example, we have three switches named 1,2 and 3 from top to down, 1 is connected with 2, 2 is connected with 3 and 3 is connected with 1 to connect a ring topology. We will configure the priority value with this commands:
switch 1 priority 15
switch 2 priority 14
switch 3 priority 13
in this case switch 2 will keep his stack-member-number 2, regardless at which time the device is rebooting or powered on. This is important because the configuration is shared on all switches within the StackWise Cluster and we don’t want to have similar port configurations on switch-members where the specific devices aren’t connected. Let us see this example:
As you can see we are using two StackWise switches with the same model. The upper switch has ethernet ports defined from 1/0/1 to 1/0/24. The bottom switch has the ports 2/0/1 to 2/0/24. So the stack number defines the first backbone-number in the gigabitEthernet port name. When you didn’t configure the priorit values, the master election will always select the switch with the longest uptime as the master. Let us consider, that the first switch is a master and the second one (top-down) is the slave, if both switches are powered down and you first start the bottom one and after seconds the top one: The bottom switch will become the master node (port-configuration 1/../..) and the top one will be elected to a slave node with ID #2 (port-configuration 2/../..). When both switches are configured as a mirror, you will have no problem, but if the ports are configured different, you will get problems.
You can also stack different models together or can pre-configure a cluster configuration by just adding this line to your configuration:
switch 2 provision ws-c3750x-12s
In this case, the IOS knows that there will be another switch clustered together and the C3750X-12S has twelve ports, so you can see that another twelve ports are coming up to be configured. At the moment you connect a fresh 3750-X-12S Catalyst switch, the device will add himself to the Stack, reboots and the pre-configured ports can be used directly.
To view and verify you stack-healthness you can use this command:
CoreSwitch# show platform stack-manager all
I hope I could explain as much as you need feel free to add comments and help me to complete this guide and explainations. I will add a new post for switch virtualization built with HP A5500 switches soon.
source: https://networkguy.de/stackwise-configuration-with-cisco-catalyst-3750-x-series/
3)
I figured the glitch,
as ridiculous as it sounds, you need to carry the same config on both members of the port channel.
so whatever you put on your port channel you need to copy it to each indidvi.. member.
The same is not true when you are trying to make a VSL, you don't need to copy the same config from the port channel(VSL channel), to members.
