You do not want to have portfast set on a LAG between switches or routers. Portfast is intended for use on ports connecting to end devices: laptop, desktop or server. If you set portfast on a connection between switches you are enabling the network to create loops which can degrade performance or shutdown the network.
When setting up a LAG between devices you will want the same amount of ports and cable connected on both ends of the connection. I see ports 1 & 2 are port-channel 1 on the 248 switch and only port 25 is port-channel 1 on the 253 switch.
The purpose of a LAG is to group multiple physical ports together to act as one virtual port.
Here is a definition of Link Aggregation:
Link Aggregation Groups or IEEE 802.1AX-2008 is a computer networking term which describes using multiple network cables/ports in parallel to increase the link speed beyond the limits of any one single cable or port, and to increase the redundancy for higher availability.
The benefits of Link Aggregation include:
Increased Availability — If a link within a LAG fails or is replaced, the traffic is not disrupted and communication is maintained (even though the available capacity is reduced).
Load Sharing — Traffic is distributed across multiple links, minimizing the probability that a single link be overwhelmed.
Use of Existing Hardware — Firmware replaces the need to upgrade the hardware to higher bandwidth capacity.
Also when a physical port is associated with a port-channel you do not have any configuration on the individual physical port. Just the commands to set up the channel-group. Then you move the port-channel to set up any switchport commands that are needed.
Thanks. I have been reading a bit on port settings and was headed that way. Good to hear from someone who has been there.
I have configed two ports on one switch and four on the other for testing different settings (moving cable). I am currently testing the new switch with two workstations. There are no errors in statistics for the port-cahnnel- is there a better way to test? maybe monitoring speed?
I can ping and browse out all across our network. Looks like the original 253 switch is taking care of all the routing.
Ping is a good indication that everything is communicating properly. You can use something like Wire Shark to monitor the traffic that is going through also.
Thanks again. I have used Wire Shark to monitor a device- but have not looked at it in awhile. Obviously not to its capacity. I had expected more forum member input, so I do appreciate your time. Maybe the word newbie turned them off.
I have had my workstation and laptop on the switch for two days- will cut the office over tomorrow.
DELL-Willy M
802 Posts
1
January 16th, 2013 09:00
You do not want to have portfast set on a LAG between switches or routers. Portfast is intended for use on ports connecting to end devices: laptop, desktop or server. If you set portfast on a connection between switches you are enabling the network to create loops which can degrade performance or shutdown the network.
When setting up a LAG between devices you will want the same amount of ports and cable connected on both ends of the connection. I see ports 1 & 2 are port-channel 1 on the 248 switch and only port 25 is port-channel 1 on the 253 switch.
The purpose of a LAG is to group multiple physical ports together to act as one virtual port.
Here is a definition of Link Aggregation:
Link Aggregation Groups or IEEE 802.1AX-2008 is a computer networking term which describes using multiple network cables/ports in parallel to increase the link speed beyond the limits of any one single cable or port, and to increase the redundancy for higher availability.
The benefits of Link Aggregation include:
Increased Availability — If a link within a LAG fails or is replaced, the traffic is not disrupted and communication is maintained (even though the available capacity is reduced).
Load Sharing — Traffic is distributed across multiple links, minimizing the probability that a single link be overwhelmed.
Use of Existing Hardware — Firmware replaces the need to upgrade the hardware to higher bandwidth capacity.
Also when a physical port is associated with a port-channel you do not have any configuration on the individual physical port. Just the commands to set up the channel-group. Then you move the port-channel to set up any switchport commands that are needed.
Edisto Kid
3 Posts
0
January 17th, 2013 06:00
Thanks. I have been reading a bit on port settings and was headed that way. Good to hear from someone who has been there.
I have configed two ports on one switch and four on the other for testing different settings (moving cable). I am currently testing the new switch with two workstations. There are no errors in statistics for the port-cahnnel- is there a better way to test? maybe monitoring speed?
I can ping and browse out all across our network. Looks like the original 253 switch is taking care of all the routing.
DELL-Willy M
802 Posts
1
January 17th, 2013 10:00
Ping is a good indication that everything is communicating properly. You can use something like Wire Shark to monitor the traffic that is going through also.
Edisto Kid
3 Posts
0
January 18th, 2013 05:00
Thanks again. I have used Wire Shark to monitor a device- but have not looked at it in awhile. Obviously not to its capacity. I had expected more forum member input, so I do appreciate your time. Maybe the word newbie turned them off.
I have had my workstation and laptop on the switch for two days- will cut the office over tomorrow.