Specifies the maximum hop count of a BPDU until the BPDU is discarded in the specified MSTP STP domain.
| stpd_name | Specifies an STPD name on the switch. |
| hopcount | Specifies the number of hops required to age out information and notify changes in the topology. The default is 20 hops, and the range is 6 to 40 hops. |
The default hop count of a BPDU is 20 hops.
This command is applicable only in an MSTP environment.
If your STPD has the same name as another component, for example a VLAN, Extreme Networks recommends that you specify the identifying keyword as well as the name. If your STPD has a name unique only to that STPD, the keyword stpd is optional.
You should not configure any STP parameters unless you have considerable knowledge and experience with STP. The default STP parameters are adequate for most networks.
The range for the hopcount parameter is 6 through 40 hops.
In an MSTP environment, the hop count has the same purpose as the maxage timer for 802.1D and 802.1w environments.
The main responsibility of the CIST is to exchange or propagate BPDUs across regions. The switch assigns the CIST an instance ID of 0, which allows the CIST to send BPDUs for itself in addition to all of the MSTIs within an MSTP region. Inside a region, the BPDUs contain CIST records and piggybacked M-records. The CIST records contain information about the CIST, and the M-records contain information about the MSTIs. Boundary ports only exchange CIST record BPDUs.
On boundary ports, only CIST record BPDUs are exchanged. In addition, if the other end is an 802.1D or 802.1w bridge, the maxage timer is used for interoperability between the protocols.
The following command sets the hop of the MSTP STPD, STPD2, to 30 hops:
configure stpd stpd2 max-hop-count 30
This command was first available in ExtremeXOS 11.4.
This command is available on ExtremeSwitching X435, X440-G2, X450-G2, X460-G2, X465, X590, X620, X690, and X695 series switches.