Solved

spanning tree on 2960s

Posted on 2014-02-19
8
235 Views
Last Modified: 2014-03-07
I have  2 2960s and they have 2 links connect to each other. I checked spanning tree and they both in the forwarding state. Shouldn't one be blocked? Thanks
0
Comment
Question by:leblanc
  • 3
  • 2
  • 2
  • +1
8 Comments
 
LVL 9

Accepted Solution

by:
ffleisma earned 200 total points
ID: 39872547
on the root bridge, depending on which is elected as the root bridge, you'll see both ports as forwarding as these ports are designated ports

if you try and look at the other switch, you should see one of the ports in blocking state and one in forwarding state, which is the root port.

also, have you configured the swithcport connections are trunks and not access ports?
0
 
LVL 9

Assisted Solution

by:ffleisma
ffleisma earned 200 total points
ID: 39872548
Spanning Tree
0
 
LVL 57

Expert Comment

by:giltjr
ID: 39873127
If you look at both switches and the both show both ports in forwarding state, then you most likely have them configured in a Etherchannel.

When you do this logically you have one port even though you really have multiple physical ports.
0
 
LVL 1

Author Comment

by:leblanc
ID: 39874749
I see. I looked on the other switch and it is indeed blocked and I think this is a mistake because we want to use both links to maximize the throughput. I will need to configure etherchannel on my switch stack. Thx
0
Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

 
LVL 57

Assisted Solution

by:giltjr
giltjr earned 200 total points
ID: 39874825
Yes, to use both connections you need to configure them as a Etherchannel.

However, you won't get a true 50/50 split.   Etherchannel does not balance on per Ethernet frame or TCP Packet or UDP datagram.

The options for "port-channel load-balance"  are:

dst-ip
dst-mac
src-dst-ip
src-dst-mac
src-ip
src-mac

Default is src-mac.  We always change to src-dst-ip on devices that don't support src-dst-port.  I think the 2960 supports src-dst-ip, but it does not support src-dst-port.
0
 
LVL 1

Author Comment

by:leblanc
ID: 39874876
Is  src-dst-ip or  src-dst-port better?
0
 
LVL 57

Assisted Solution

by:giltjr
giltjr earned 200 total points
ID: 39874897
src-dst-port is better, but not all devices support it.

src-dst-ip says to balance based on src and dst IP address.

src-dst-port says to balance based on src ipaddress:port and dst ipaddress:port.

With src-dst-ip if two hosts have multiple tcp connections to each other, all of them will go over the same physical connection.

With src-dst-port  if two hosts have multiple tcp connections to each other, each connection can go across a different physical connections.
0
 
LVL 45

Assisted Solution

by:Craig Beck
Craig Beck earned 100 total points
ID: 39876462
If you're using trunks you might see that both links are up but some VLANs are blocked on each link, depending on how you configure STP per-VLAN on each switch.

Obviously you've got this one sorted, but I just thought it might help in the future.
0

Featured Post

Windows Server 2016: All you need to know

Learn about Hyper-V features that increase functionality and usability of Microsoft Windows Server 2016. Also, throughout this eBook, you’ll find some basic PowerShell examples that will help you leverage the scripts in your environments!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Why APC patch cords are not recommended wirth 10GBase SFP+ Gbics? 6 69
Installation of Nessus Professional 5 80
logging buffered 8 37
Hyper-V VM not connected 1 75
Don’t let your business fall victim to the coming apocalypse – use our Survival Guide for the Fax Apocalypse to identify the risks and signs of zombie fax activities at your business.
Most of the applications these days are on Cloud. Cloud is ubiquitous with many service providers in the market. Since it has many benefits such as cost reduction, software updates, remote access, disaster recovery and much more.
Here's a very brief overview of the methods PRTG Network Monitor (https://www.paessler.com/prtg) offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…

929 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

14 Experts available now in Live!

Get 1:1 Help Now