Cisco Miscellany

interface FastEthernet2/0/1
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 100
 switchport mode trunk
 switchport voice vlan 2
 srr-queue bandwidth share 10 10 60 20
 srr-queue bandwidth shape 10 0 0 0
 mls qos trust cos
 auto qos voip trust
 spanning-tree portfast trunk

What does this mean?

Interface (port) running at 100MBs of identity Switch 2 / Stack 0 ?? / Port 1 has the following characteristics:

It is a trunk and its encapsulation is 802.1Q. Its native to VLAN 100 but will accept traffic from other VLANS too. It is configured to handle traffic from VLAN 2 (i.e. VOIP devices) differently that other traffic. This is shown with the bandwidth shaping and bandwidth sharing.

Each interface has 4 queues (this is known as egress queuing). You can specify what share of the bandwidth by issuing it a ratio of the total bandwidth. So srr-queue bandwidth share 10 10 60 20 would assign 60% of the bandwidth to queue 3.

The shaping command works differently as it denotes a percentage. Queue 1 in the output above will only be able to use 10% of the bandwidth.

The lines containing QoS relate to prioritising the VOIP traffic. The COS identifier (a value originating from the header of frames) is used to identify VOIP traffic which is then given priority over data frames.


It looks as though the VOIP traffic uses queue 1 because it is shaped and allows for "smoother" traffic flow.

Useful links:

https://supportforums.cisco.com/thread/165677

Cisco + NetApp + VMware p1

I have a free NetApp FAS2050, a very old Cisco 2950 100mb switch and a HP DL380 server. Can I make them work together?

My objective is to run ESXi 5.1 on the HP server with two guests (an Exchange 2010 server and a domain controller). The server only has 2 NICs unfortunately: one of them will be used for iSCSI and the other management. The NetApp must be configured in one big RAID 10 volume. They must communicate through the 2950.


The Cisco 2950

Log in as a super user:

en ↵
[password] ↵

The "show" command followed by "?" will display all the informational commands. To start off, good informational commands:

show running-config ↵
show interface status ↵ 

The switch that I picked up has most of its ports set to VLan 100, but I want VLan 302 because that is what the NetApp is set to. To create a VLan:

conf t ↵
vlan 302 ↵
name iSCSi ↵
Ctrl Z

Now to assign a port (or two) to the previously created VLan:

conf t ↵
int fa0/1 ↵
switchport mode access ↵
switchport access vlan 302 ↵
Ctrl Z

If you wanted to make that port a trunk you would have entered:

switchport mode trunk ↵

A trunk can accept multiple VLan traffic:

switchport trunk allowed vlan 100,302,303
 
I cheated a bit in the end. I had the config from the switch the NetApp used to be plugged into. From that I determined how the ports should be configured. This is the port configuration that I copied:

interface GigabitEthernet0/7
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 100,302,303
switchport mode trunk
spanning-tree portfast

After this the NetApp could be pinged and I could connect to it via putty.