When to use spanning-tree portfast trunk
Usually spanning-tree portfast is used on access port to which a computer is connected , in order to avoid the 50 Seconds of STP. However I saw examples where they use it on a Trunk Port. I wonder if STP runs on a Trunk and if so why would they disable it with portfast or type edge (Nexus) ?
CISCO-IOS
spanning-tree portfast (for an access port)
spanning-tree portfast trunk (for a trunk port)
◦NX-IOS
spanning-tree port type edge (for an access port)
spanning-tree port type edge trunk (for a trunk port
CISCO-IOS
spanning-tree portfast (for an access port)
spanning-tree portfast trunk (for a trunk port)
◦NX-IOS
spanning-tree port type edge (for an access port)
spanning-tree port type edge trunk (for a trunk port
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER CERTIFIED SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
I was not sure about the Network Adapter on ESX server that it understands Trunk. So the ESX Network Adapter is not like regular computer 's Network Adapter ?
if a Switch is connected to a computer, and configure the Link as Trunk , would the computer still communicate with switch as if it the link was configured as Access port ?
if a Switch is connected to a computer, and configure the Link as Trunk , would the computer still communicate with switch as if it the link was configured as Access port ?
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
If a switchport is configured as a trunk but the connected computer is not, then the computer will communicate over the native VLAN.
OK
It will be just like an access port with no specific Vlan
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
Thank you Guys!
You can disable spanning tree (enable portfast)
BTW, portfast does not disable spanning-tree. It simply bypasses the initial listening/learning states. Spanning-tree is still sending and processing BPDU's on a port with portfast enabled on it.
@ Don Johnson
It is easier to just say disable. From years of experience, it has proven to help people understand the process faster.
There's about 300page documentation on spanning tree. Most engineers don't care about the details. The most common concept for spanning tree is whether redundant port is blocked or not. To disable ports being blocked, you enable portfast.
Just "keep it simple"
It is easier to just say disable. From years of experience, it has proven to help people understand the process faster.
There's about 300page documentation on spanning tree. Most engineers don't care about the details. The most common concept for spanning tree is whether redundant port is blocked or not. To disable ports being blocked, you enable portfast.
Just "keep it simple"
It is easier to just say disable.It's also easier to say that airplanes fly because of anti-gravity engines. While that may make it easier explaining an airplane to children, it's not very useful when dealing with student pilots.
From years of experience, it has proven to help people understand the process faster.And not a month goes by that I don't have someone in class that has a misunderstanding on a fundamental concept in networking that I have to correct.
Your statement was an absolute. Meaning there was no preface of "the behavior is similar to..." or "it works like..." Leading to the assumption that portfast disables spanning tree... which it does not.
There's about 300page documentation on spanning tree.373 pages to be exact (1998 revision). :-)
Most engineers don't care about the details.I think that you'll find a lot of people here (if they're not engineers) do care about the details.
To disable ports being blocked, you enable portfast.Not correct. A port with portfast enabled will block if the spanning-tree algorithm determines it should block.
Just "keep it simple"I prefer to "keep it correct".
ASKER
Usually ports connected to computers are configured as Access ports with portfast, but ESX uses the concept of Vlans too, but I wonder if it can cause loop to Cisco switch that it is connecting to ?