hosts per vlan with juniper switches

I inherited a network will all Juniper switches EX series. I notice that there are about 40 vlans and the subnets are /16. Isn't it too many hosts per vlan? What could go wrong in this case? From my understanding rstp is the default spanning tree on the Juniper. Now if there is convergence with rstp, it will affect the whole network and not just the vlan in per vlan stp. Correct? If yes, should I redesigned my rstp to per vlan rstp? Thanks in advance for your inputs.
LVL 1
leblancAccountingAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Don JohnstonInstructorCommented:
I inherited a network will all Juniper switches EX series. I notice that there are about 40 vlans and the subnets are /16. Isn't it too many hosts per vlan? What could go wrong in this case?
The mask size only defines how many hosts could exist on a network. There could only be 50 hosts of the network. But with that mask, you could have 64,000.  The primary issue these days with large broadcast domains is excessive broadcast traffic.  In that case, you would see reduced bandwidth available and all hosts processing large volumes of broadcast traffic.

From my understanding rstp is the default spanning tree on the Juniper. Now if there is convergence with rstp, it will affect the whole network and not just the vlan in per vlan stp. Correct?
Yes. In a Common (or mono) Spanning Tree environment, there is only one instance of STP.  So if the network re-converges, it will affect traffic in all VLANs.

If yes, should I redesigned my rstp to per vlan rstp? Thanks in advance for your inputs.
I wouldn't say "should".  A Per-VLAN STP  (VSTP in Juniper parlance) environment is typically used to allow you to define different root bridges and path costs on a per-VLAN basis. That way you can control which ports are forwarding/blocking to provide better paths for the hosts.  Since in most multi-VLAN environments the VLANs cross common trunks, a failure causing re-convergence will most likely affect all VLANs.
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Switches / Hubs

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.