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Re: STP on V1910-24G forwarding and blocking ports

 
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MartinWoodhouse
Visitor

STP on V1910-24G forwarding and blocking ports

Hello,

 

Please excuse any incorrect terminology, networking isn't my specialty! 

 

We are running two V1910-24G (JE006A) switches in our core (small) network with redundant uplinks to our provider, each switch has an uplink to our provider and a link between the switches. 

 

All of the connections are running at Gigabit Ethernet, our provider has rootguard enable on their switches so we have a lower priority set on our bridge to prevent our switches trying to become the root of the network, this is all working fine, but currently our switches have both of our providers ports set to Forwarding and one switch has the interswitch cable set to Forwarding and the other is Discarding, we would prefer that connectivity between our switches went directly between our switches rather than using our providers network equipment.

 

I queried this with them and they mentioned to set the Port Priority to 19 or higher on one of the uplinks to them, so that our switch would prefer our internal link instead of theirs, I've made these changes and tried 18/19 or 21/22 to see if my interpretation of higher was different to theirs, but this hasn't made any difference the configuration remains the same, I'd just like to check here that everything looks correct before I go back to them with it, since I could be missing something.

 

Please see my current configuration:

 

Switch One (port one is uplink, two is interswitch):

 

----[Port1(GigabitEthernet1/0/1)][FORWARDING]----
Port Protocol :enabled
Port Role :CIST Root Port
Port Priority :128
Port Cost(Legacy) :Config=19 / Active=19

 

----[Port2(GigabitEthernet1/0/2)][FORWARDING]----
Port Protocol :enabled
Port Role :CIST Designated Port
Port Priority :128
Port Cost(Legacy) :Config=20 / Active=20

 

Switch Two (port one is uplink, two is interswitch):

 

----[Port1(GigabitEthernet1/0/1)][FORWARDING]----
Port Protocol :enabled
Port Role :CIST Root Port
Port Priority :128
Port Cost(Legacy) :Config=21 / Active=21

 

----[Port2(GigabitEthernet1/0/2)][DISCARDING]----
Port Protocol :enabled
Port Role :CIST Alternate Port
Port Priority :128
Port Cost(Legacy) :Config=20 / Active=20

 

I would greatly appreciate any help that you could recommend. 

 

Kind Regards,

Martin

 

 

P.S. This thread has been moved from ProCurve / ProVision-Based to Web and Unmanaged - Hp forum Moderator

2 REPLIES 2
Richard Brodie_1
Honored Contributor
Solution

Re: STP on V1910-24G forwarding and blocking ports

It makes a big difference whether you are changing priority or cost. You say one Priority  in the text but the configuration shows altered Cost. Often people post here with priority settings, which often make no difference at all; it's more or less a tie-breaker.

 

Anyway, what you need to do is to convince one of the nodes that the shortest path to the root is via the other node and not direct. By default it's going to be 20 direct, or 40 indirect. So you need to do something like bump the uplink cost to 50 on one of the switches.

MartinWoodhouse
Visitor

Re: STP on V1910-24G forwarding and blocking ports

Hello,

 

Sorry, I should have listed Cost not Priority, but I kept getting the two confused and should have re-read my post before posting, I researched that the Priority affects the remote device rather than the local one and it was cost that I should have and was trying to use. 

 

I've increased the Cost on one of my uplinks to 50 and that has fixed the problem, you are a star, thank you! 

 

Kind Regards,

Martin