RSTP and maximum devices

I'm building a ring with 40 RGS-200 12P switches and an XGS2220 core. 
Can I make an RSTP ring with all this devices? 
What is the limit on the number of devices?
Is there a subtlety to integrate into the settings?

Thanks.

Accepted Solution

All Replies

  • Zyxel_Melen
    Zyxel_Melen Posts: 1,628  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer

    Hi @GoatLy,

    The maximum device number of RSTP is 16.

    To fulfill your requirement, you can use the Ringv2 function on RGS-200 for redundancies and prevent loops. And connect XGS2220 with one of the RGS-200s in the ring since it is your core switch.

    Zyxel Melen

  • Hello Melen,

    Thanks for answer. I have more questions now :)

    1 - What will happen if I put more than 16 pieces of equipment? Won't this just lengthen the convergence time?

    2 - with Ringv2, can I create a ring with my 40 RGS220 and my XGS2220? I found little documentation on this. Will this replace RSTP? Do you have a full doc about this ?

    Thanks !

  • Zyxel_Melen
    Zyxel_Melen Posts: 1,628  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer
    edited September 2023

    Hi @GoatLy,

    1 - What will happen if I put more than 16 pieces of equipment? Won't this just lengthen the convergence time?

    If you have more than that number, the STP convergency cannot be finished and that will cause problems in the network.

    2 - with Ringv2, can I create a ring with my 40 RGS220 and my XGS2220? I found little documentation on this. Will this replace RSTP? Do you have a full doc about this ?

    Since XGS2220 does not support Ringv2 (a.k.a. Fast Failover Ring Protection), you cannot place it in the ring with RGS200. It will cause loops if you add XGS2220 to the ring.

    Here's the step to set up the Ringv2:

    1. Access the master of your RGS-200, navigate to Configuration > Ringv2 to enable Index 1, change the role to Ring(Master), and configure the Forward port and Block port.
    2. Access other RGS-200s, navigate to Configuration > Ringv2 to enable Index 1, change the role to Ring(Slave), and configure the Forward ports.

    Note: Please do not connect the ring before finishing the setting, otherwise loops will occur.

    Hope it helps.

    Zyxel Melen

  • Hello,

    Thanks, it's muche clearer !
    Last question : so, if a fiber is cut somewhere in the ring, the blocked port on the primary will go to forward state?

    Thanks.

  • Zyxel_Melen
    Zyxel_Melen Posts: 1,628  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer
    Answer ✓

    Hi @GoatLy,

    Correct. The blocked port will change to forwarding state once the ring is broken.

    For more information, please reference this FAQ

    Zyxel Melen