Knowledge Search


×
 

[EX] Difference in RSTP default configuration between EX switches and EX ELS switches

  [KB33693] Show Article Properties


Summary:

There are differences in the way default Rapid Spanning Tree Protocol (RSTP) configuration is executed in EX switches and EX ELS switches, which are not evident from the configuration itself.

This article differentiates interface behavior when default RSTP configuration is used in these two switches.

 

Solution:

It is necessary to keep the following difference in mind while configuring RSTP in the specified switches.

EX legacy platforms have an implicit "interface all" setting when it comes to default configuration. So with the following default configuration, every interface that is configured with the family ethernet-switching will be a part of RSTP.

root@switch#  show protocols 
igmp-snooping {
    vlan all;
}
rstp;
lldp {
    interface all;
}

On a legacy EX platform, the above configuration would mean that RSTP is enabled for all interfaces with the family ethernet-switching, whereas on ELS platforms, this configuration would mean that no interface is part of RSTP.

On ELS platforms, the interface all setting is not "implicit." Therefore, if the interfaces are not set explicitly in the configuration, as shown below, no interface will be part of RSTP.

root@switchELS#show protocols
lldp {
    interface all;
}
lldp-med {
    interface all;
}
igmp-snooping {
    vlan default;
}
rstp {
    interface ge-0/0/0;
    interface ge-0/0/1;
    interface ge-0/0/2;
    interface ge-0/0/3;
    interface ge-0/0/4;
    interface ge-0/0/5;
    interface ge-0/0/6;
}
 

Note: From Junos OS version 15.1, the interface all option has been added for RSTP on ELS platforms.

 

Related Links: