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... P T E R 6 C H A P T E R 78-15486-01 Configuring Gigabit Ethernet Switching 5-1 Understanding How Gigabit Ethernet Works 5-1 Understanding How Gigabit Ethernet Flow Control Works 5-1 Understanding How Port ... Tree Port Cost 6-8 Setting the EtherChannel Spanning Tree Port VLAN Cost 6-9 Removing an EtherChannel Bundle 6-9 Displaying EtherChannel Configuration Information 6-10 Displaying EtherChannel Traffic Statistics 6-11 Displaying EtherChannel PAgP Statistics 6-12 EtherChannel Configuration Examples 6-12 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration ...
... P T E R 6 C H A P T E R 78-15486-01 Configuring Gigabit Ethernet Switching 5-1 Understanding How Gigabit Ethernet Works 5-1 Understanding How Gigabit Ethernet Flow Control Works 5-1 Understanding How Port ... Tree Port Cost 6-8 Setting the EtherChannel Spanning Tree Port VLAN Cost 6-9 Removing an EtherChannel Bundle 6-9 Displaying EtherChannel Configuration Information 6-10 Displaying EtherChannel Traffic Statistics 6-11 Displaying EtherChannel PAgP Statistics 6-12 EtherChannel Configuration Examples 6-12 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration ...
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... Specifying the Port Priority 6-19 Specifying an Administrative Key Value 6-19 Changing the Channel Mode 6-20 Specifying the Channel Path Cost 6-21 Specifying the Channel VLAN Cost 6-21 Clearing LACP Statistics 6-21 Displaying EtherChannel Traffic Utilization 6-21 Disabling an EtherChannel 6-22 Displaying Spanning Tree-Related Information for... Rapid Spanning Tree Protocol 7-16 MST-to-SST Interoperability 7-17 Common Spanning Tree 7-18 MST Instances 7-18 MST Configuration 7-18 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 vi 78-15486-01
... Specifying the Port Priority 6-19 Specifying an Administrative Key Value 6-19 Changing the Channel Mode 6-20 Specifying the Channel Path Cost 6-21 Specifying the Channel VLAN Cost 6-21 Clearing LACP Statistics 6-21 Displaying EtherChannel Traffic Utilization 6-21 Disabling an EtherChannel 6-22 Displaying Spanning Tree-Related Information for... Rapid Spanning Tree Protocol 7-16 MST-to-SST Interoperability 7-17 Common Spanning Tree 7-18 MST Instances 7-18 MST Configuration 7-18 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 vi 78-15486-01
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...Default PVST+ Configuration 7-23 Setting the PVST+ Bridge ID Priority 7-23 Configuring the PVST+ Port Cost 7-25 Configuring PVST+ Port Priority 7-25 Configuring the PVST+ Default Port Cost Mode 7-26 Configuring the PVST+ Port VLAN Cost 7-26 Configuring the PVST+ Port VLAN Priority 7-27 Disabling the PVST+ Mode on a VLAN ... Tree BPDU Skewing 7-57 Configuring Spanning Tree PortFast, BPDU Guard, BPDU Filter, UplinkFast, BackboneFast, and Loop Guard 8-1 Understanding How PortFast Works 8-1 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 vii
...Default PVST+ Configuration 7-23 Setting the PVST+ Bridge ID Priority 7-23 Configuring the PVST+ Port Cost 7-25 Configuring PVST+ Port Priority 7-25 Configuring the PVST+ Default Port Cost Mode 7-26 Configuring the PVST+ Port VLAN Cost 7-26 Configuring the PVST+ Port VLAN Priority 7-27 Disabling the PVST+ Mode on a VLAN ... Tree BPDU Skewing 7-57 Configuring Spanning Tree PortFast, BPDU Guard, BPDU Filter, UplinkFast, BackboneFast, and Loop Guard 8-1 Understanding How PortFast Works 8-1 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 vii
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Command set port name mod_num/port_num [name_string] show port [mod_num[/port_num]] 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 4-3 Setting Ethernet and Fast Ethernet Port Names You can assign names to the ports on configuring Fast EtherChannel, see...8226; Autonegotiate duplex for 100-Mbps Fast Ethernet ports VLAN 1 • Port cost of 100 for 10-Mbps Ethernet ports • Port cost of 19 for 10/100-Mbps Fast Ethernet ports • Port cost of 19 for 100-Mbps Fast Ethernet ports Disabled on all Fast Ethernet ports (...
Command set port name mod_num/port_num [name_string] show port [mod_num[/port_num]] 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 4-3 Setting Ethernet and Fast Ethernet Port Names You can assign names to the ports on configuring Fast EtherChannel, see...8226; Autonegotiate duplex for 100-Mbps Fast Ethernet ports VLAN 1 • Port cost of 100 for 10-Mbps Ethernet ports • Port cost of 19 for 10/100-Mbps Fast Ethernet ports • Port cost of 19 for 100-Mbps Fast Ethernet ports Disabled on all Fast Ethernet ports (...
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...are enabled Port name None Port priority Normal Duplex mode Full duplex Flow control • Oversubscribed Gigabit Ethernet ports (ports 3-18 on WS-X4418-GB): Flow control set to desired for receive (Rx) and on for transmit (Tx) • All others: Flow ...for transmit (Tx) Port negotiation Enabled Spanning Tree Protocol Enabled for VLAN 1 Native VLAN VLAN 1 Spanning tree port cost 4 Gigabit EtherChannel Disabled on all Gigabit Ethernet ports (auto mode) Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 5-6 78-15486-01
...are enabled Port name None Port priority Normal Duplex mode Full duplex Flow control • Oversubscribed Gigabit Ethernet ports (ports 3-18 on WS-X4418-GB): Flow control set to desired for receive (Rx) and on for transmit (Tx) • All others: Flow ...for transmit (Tx) Port negotiation Enabled Spanning Tree Protocol Enabled for VLAN 1 Native VLAN VLAN 1 Spanning tree port cost 4 Gigabit EtherChannel Disabled on all Gigabit Ethernet ports (auto mode) Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 5-6 78-15486-01
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Setting different port path costs does not, by the set spantree portcost command, can change causes all existing EtherChannels to reset to full duplex. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-3 the show spantree command. the ports do not...This discrepancy exists because the port is suppressed. Instead of an EtherChannel. • PAgP and LACP manage channels differently. Note Switches can be contiguous or on mode. • You can form an EtherChannel as long as "not connected" using the show...
Setting different port path costs does not, by the set spantree portcost command, can change causes all existing EtherChannels to reset to full duplex. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-3 the show spantree command. the ports do not...This discrepancy exists because the port is suppressed. Instead of an EtherChannel. • PAgP and LACP manage channels differently. Note Switches can be contiguous or on mode. • You can form an EtherChannel as long as "not connected" using the show...
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... range of service (QoS) configurations. • An EtherChannel will not form with different VLAN costs or VLAN configurations cannot form a channel. Note With software release 6.3(1) and later releases, a... prior to 6.3(1), traffic was disrupted when you must set differently on the ports. • Cisco Discovery Protocol (CDP) runs on the physical port even after the port is added to a... LACP to spanning tree as dynamic VLAN ports. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-4 78-15486-01 Configuring ports in an EtherChannel...
... range of service (QoS) configurations. • An EtherChannel will not form with different VLAN costs or VLAN configurations cannot form a channel. Note With software release 6.3(1) and later releases, a... prior to 6.3(1), traffic was disrupted when you must set differently on the ports. • Cisco Discovery Protocol (CDP) runs on the physical port even after the port is added to a... LACP to spanning tree as dynamic VLAN ports. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-4 78-15486-01 Configuring ports in an EtherChannel...
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... • Defining an EtherChannel Administrative Group, page 6-7 • Setting the EtherChannel Spanning Tree Port Cost, page 6-8 • Setting the EtherChannel Spanning Tree Port VLAN Cost, page 6-9 • Removing an EtherChannel Bundle, page 6-9 • Displaying EtherChannel Configuration Information, page...EtherChannel. EtherChannel IDs are stored in NVRAM and remain the same after the switch is reset or power cycled. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-6 78-15486-01 Understanding Administrative Groups and ...
... • Defining an EtherChannel Administrative Group, page 6-7 • Setting the EtherChannel Spanning Tree Port Cost, page 6-8 • Setting the EtherChannel Spanning Tree Port VLAN Cost, page 6-9 • Removing an EtherChannel Bundle, page 6-9 • Displaying EtherChannel Configuration Information, page...EtherChannel. EtherChannel IDs are stored in NVRAM and remain the same after the switch is reset or power cycled. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-6 78-15486-01 Understanding Administrative Groups and ...
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...1 Step 2 Task Command Determine the EtherChannel ID of the EtherChannel show channel group admin_group for which you want to set the EtherChannel port path cost for an EtherChannel set port channel 3/5-6 50 Port(s) 3/5-6 are assigned to admin group 50. Console> (enable) show channel group 50 Admin... on 768 20 1/2 connected on 768 Admin Port Device-ID Port-ID Platform group 20 1/1 20 1/2 066510644(cat26-lnf(NET25)) 2/1 WS-C6009 Console> (enable) Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-8 78-15486-01
...1 Step 2 Task Command Determine the EtherChannel ID of the EtherChannel show channel group admin_group for which you want to set the EtherChannel port path cost for an EtherChannel set port channel 3/5-6 50 Port(s) 3/5-6 are assigned to admin group 50. Console> (enable) show channel group 50 Admin... on 768 20 1/2 connected on 768 Admin Port Device-ID Port-ID Platform group 20 1/1 20 1/2 066510644(cat26-lnf(NET25)) 2/1 WS-C6009 Console> (enable) Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-8 78-15486-01
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...the remaining VLANS in Step 1. Set the spanning tree port VLAN cost for channel ID 768: Console> (enable) show port channel [mod_num[/port_num]] 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-9 Warning:channel cost may not be applicable if channel is set channel vlancost {channel_id ...perform this task on 768 Admin Port Device-ID Port-ID Platform group 20 1/1 20 1/2 066510644(cat26-lnf(NET25)) 2/1 WS-C6009 Console> (enable) Console> (enable) set channel vlancost 768 12 Channel 768 vlancost set channel...
...the remaining VLANS in Step 1. Set the spanning tree port VLAN cost for channel ID 768: Console> (enable) show port channel [mod_num[/port_num]] 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-9 Warning:channel cost may not be applicable if channel is set channel vlancost {channel_id ...perform this task on 768 Admin Port Device-ID Port-ID Platform group 20 1/1 20 1/2 066510644(cat26-lnf(NET25)) 2/1 WS-C6009 Console> (enable) Console> (enable) set channel vlancost 768 12 Channel 768 vlancost set channel...
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...; Specifying the Channel Path Cost, page 6-21 • Specifying the Channel VLAN Cost, page 6-21 • Clearing LACP Statistics, page 6-21 • Displaying EtherChannel Traffic Utilization, page 6-21 • Disabling an EtherChannel, page 6-22 • Displaying Spanning Tree-Related Information for all modules. 6-18 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78...
...; Specifying the Channel Path Cost, page 6-21 • Specifying the Channel VLAN Cost, page 6-21 • Clearing LACP Statistics, page 6-21 • Displaying EtherChannel Traffic Utilization, page 6-21 • Disabling an EtherChannel, page 6-22 • Displaying Spanning Tree-Related Information for all modules. 6-18 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78...
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...statistics, perform this task: Task Display traffic utilization. For more information, see the "Setting the EtherChannel Spanning Tree Port Cost" section on page 6-9 for information. Command show lacp-channel traffic ChanId Port Rx-Ucst Tx-Ucst Rx-Mcst Tx-Mcst...% 0.00% 816 2/32 0.00% 0.00% 75.75% 50.50% 0.00% 0.00% Console> (enable) 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-21 Chapter 6 Configuring Fast EtherChannel and Gigabit EtherChannel Configuring EtherChannel Using LACP This example shows how to change ...
...statistics, perform this task: Task Display traffic utilization. For more information, see the "Setting the EtherChannel Spanning Tree Port Cost" section on page 6-9 for information. Command show lacp-channel traffic ChanId Port Rx-Ucst Tx-Ucst Rx-Mcst Tx-Mcst...% 0.00% 816 2/32 0.00% 0.00% 75.75% 50.50% 0.00% 0.00% Console> (enable) 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 6-21 Chapter 6 Configuring Fast EtherChannel and Gigabit EtherChannel Configuring EtherChannel Using LACP This example shows how to change ...
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... Portfast Channel_id 4/6 1 not-connected 4 32 disabled 0 Console> Console> show spantree 4/7-8 Port Vlan Port-State Cost Priority Portfast Channel_id 4/7-8 1 blocking 3 32 disabled 770 Console> 6-22 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01 Console> (enable) Displaying Spanning Tree-Related Information for EtherChannels You can display the channel ID and the...
... Portfast Channel_id 4/6 1 not-connected 4 32 disabled 0 Console> Console> show spantree 4/7-8 Port Vlan Port-State Cost Priority Portfast Channel_id 4/7-8 1 blocking 3 32 disabled 770 Console> 6-22 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01 Console> (enable) Displaying Spanning Tree-Related Information for EtherChannels You can display the channel ID and the...
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... to end stations, which they are common to all spanning tree protocols. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 7-2 78-15486-01 Spanning tree operation is ... see the "Understanding How a Topology Is Created" section on both sides of the switch. The Cisco proprietary spanning tree protocols, PVST+ and MISTP, are based on the IEEE 802.1D ... or if spanning tree costs change, the spanning tree algorithm reconfigures the spanning tree topology and reestablishes the link by placing redundant switch ports in the active ...
... to end stations, which they are common to all spanning tree protocols. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 7-2 78-15486-01 Spanning tree operation is ... see the "Understanding How a Topology Is Created" section on both sides of the switch. The Cisco proprietary spanning tree protocols, PVST+ and MISTP, are based on the IEEE 802.1D ... or if spanning tree costs change, the spanning tree algorithm reconfigures the spanning tree topology and reestablishes the link by placing redundant switch ports in the active ...
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... things determine the topology of an active switched network: • The unique switch identifier (MAC address of the switch) that is associated with each switch • The path cost to become the root switch by changing the port cost parameter for the UTP port to recalculate ... priority (that is, lowering the priority number) on the preferred switch. When the spanning tree topology is the logical center of the fiber-optic port. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 7-3 Also, another port on default parameters...
... things determine the topology of an active switched network: • The unique switch identifier (MAC address of the switch) that is associated with each switch • The path cost to become the root switch by changing the port cost parameter for the UTP port to recalculate ... priority (that is, lowering the priority number) on the preferred switch. When the spanning tree topology is the logical center of the fiber-optic port. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 7-3 Also, another port on default parameters...
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..." section on bandwidth. You can also manually assign port costs between 1-65535. This is the switch that is selected. The short method (default) will be used to the root. • A port for each switch is based on page 7-26. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 7-4 78-15486-01 Each configuration BPDU contains...
..." section on bandwidth. You can also manually assign port costs between 1-65535. This is the switch that is selected. The short method (default) will be used to the root. • A port for each switch is based on page 7-26. Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 7-4 78-15486-01 Each configuration BPDU contains...
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... Spanning Tree Port States Topology changes can create temporary data loops. When a switch port transitions directly from links that changes in bandwidth will not result in changes to the cost of the port concerned. The formula for the aggregated port. These changes in...Cost Value 100 19 4 Default Range 1 to 65535 1 to 65535 1 to 65535 Calculating the Port Cost Using the Long Method 802.1t assigns 32-bit (long) default port cost values to each port using STP is in one of these states: • Blocking 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches...
... Spanning Tree Port States Topology changes can create temporary data loops. When a switch port transitions directly from links that changes in bandwidth will not result in changes to the cost of the port concerned. The formula for the aggregated port. These changes in...Cost Value 100 19 4 Default Range 1 to 65535 1 to 65535 1 to 65535 Calculating the Port Cost Using the Long Method 802.1t assigns 32-bit (long) default port cost values to each port using STP is in one of these states: • Blocking 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches...
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... the message age increases by an instance ID that increments each time you commit the MST configuration. 7-18 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01 Setting the CST partitions to 15. each hop, the difference in...spanning tree protocol running in the neighboring SST regions because the root identifier and root cost are the same. - The root identifier and root cost are optional. In a Catalyst 4500 series switch running PVST+, the VLAN 1 spanning tree corresponds to the configuration. Instance 0 is...
... the message age increases by an instance ID that increments each time you commit the MST configuration. 7-18 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01 Setting the CST partitions to 15. each hop, the difference in...spanning tree protocol running in the neighboring SST regions because the root identifier and root cost are the same. - The root identifier and root cost are optional. In a Catalyst 4500 series switch running PVST+, the VLAN 1 spanning tree corresponds to the configuration. Instance 0 is...
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...MST region, then one of the MST bridges at each host or router. The root path cost and message age inside a region stays constant, but the IST path cost is incremented and the IST remaining hops is decremented at the boundary is selected as edge, ... However, cabling in most networks meets this requirement, and you need to start forwarding as soon as point-to -point links. 7-20 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01 Enter the set a slightly lower bridge priority to a nonbridging device (for example, a host...
...MST region, then one of the MST bridges at each host or router. The root path cost and message age inside a region stays constant, but the IST path cost is incremented and the IST remaining hops is decremented at the boundary is selected as edge, ... However, cabling in most networks meets this requirement, and you need to start forwarding as soon as point-to -point links. 7-20 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01 Enter the set a slightly lower bridge priority to a nonbridging device (for example, a host...
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...Console> (enable) show spantree mst 3 Spanning tree mode MST Instance 3 VLANs Mapped: 31-40 Designated Root Designated Root Priority Designated Root Cost Designated Root Port 00-10-7b-bb-2f-00 8195 (root priority:8192, sys ID ext:3) 0 Remaining Hops 20 1/0 Bridge ID...switches, the ports might change to the MST switch at the boundary. IST and MST use the Message Age and Maximum Age timer settings in the BPDUs (M-records) they generate. You can configure each MST bridge with a slower CPU running MST. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches...
...Console> (enable) show spantree mst 3 Spanning tree mode MST Instance 3 VLANs Mapped: 31-40 Designated Root Designated Root Priority Designated Root Cost Designated Root Port 00-10-7b-bb-2f-00 8195 (root priority:8192, sys ID ext:3) 0 Remaining Hops 20 1/0 Bridge ID...switches, the ports might change to the MST switch at the boundary. IST and MST use the Message Age and Maximum Age timer settings in the BPDUs (M-records) they generate. You can configure each MST bridge with a slower CPU running MST. 78-15486-01 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches...