stp
config>service>vpls
config>service>vpls>sap
config>template>vpls-template
Supported on all 7210 SAS platforms as described in this document
Commands in this context configure the Spanning Tree Protocol (STP) parameters.
The Nokia STP is the Spanning Tree Protocol (STP) with a few modifications to better suit the operational characteristics of VPLS services. The most evident change is to the root bridge election. Because the core network operating between the service routers should not be blocked, the root path is calculated from the core perspective.
auto-edge
no auto-edge
config>service>vpls>sap>stp
config>service>vpls>spoke-sdp>stp
Supported on all 7210 SAS platforms as described in this document
This command configures automatic detection of the edge port characteristics of the SAP.
The no form of this command reverts to the default value.
auto-edge
[no] edge-port
config>service>vpls>sap>stp
config>service>vpls>spoke-sdp>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the SAP as an edge or non-edge port. If the auto-edge command is enabled for the SAP, this value is used only as the initial value.
However, RSTP can detect that the actual situation is different from what the edge-port command may indicate.
Initially, the value of the SAP parameter is set to edge-port. This value changes in the following circumstances:
a BPDU is received on that port. This means that there is another bridge connected to this port; in this case, the edge-port becomes disabled.
auto-edge is configured and no BPDU is received within a specified period of time; RSTP concludes that it is on an edge and enables the edge-port
The no form of this command reverts to the default value.
no edge-port
forward-delay seconds
no forward-delay
config>service>vpls>stp
config>template>vpls-template>stp
Supported on all 7210 SAS platforms as described in this document
RSTP, as defined in the IEEE 802.1D-2004 standards, transitions to the forwarding state via a handshaking mechanism (rapid transition), without wait times. If handshaking fails (for example, on shared links (see the following)), the system falls back to the timer-based mechanism defined in the original STP (802.1D-1998) standard.
A shared link is a link with more than two nodes (for example, a shared 10/100BaseT segment). The port-type command is used to configure a link as point-to-point or shared.
For timer-based transitions, the 802.1D-2004 standard defines an internal variable forward-delay, which is used in calculating the default number of seconds that a SAP spends in the discarding and learning states when transitioning to the forwarding state.
The value of the forward-delay parameter depends on the STP operating mode of the VPLS instance, as described in the following:
in rstp or mstp mode, but only when the SAP has not fallen back to legacy STP operation, the value configured by the hello-time command is used
in all other situations, the value configured by the forward-delay command is used
forward-delay 15
Specifies the forward delay timer for the STP instance, in seconds.
hello-time hello-time
no hello-time
config>service>vpls>stp
config>template>vpls-template>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the STP hello time for the VPLS STP instance.
The hello-time parameter defines the default timer value that controls the sending interval between BPDU configuration messages by this bridge, on ports where this bridge assumes the designated role.
The active hello time for the spanning tree is determined by the root bridge (except when the STP is running in RSTP mode; in this case, the hello time is always taken from the locally configured parameter).
The configured hello time can also be used to calculate the forward delay. See the auto-edge command for more information.
The no form of this command reverts to the default value.
hello-time 2
Specifies the hello time for the STP instance, in seconds.
hold-count BDPU tx hold count
no hold-count
config>service>vpls>stp
config>template>vpls-template>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the peak number of BPDUs that can be transmitted in a period of one second.
The no form of this command reverts to the default value
hold-count 6
Specifies the hold count for the STP instance, in seconds.
link-type {pt-pt | shared}
no link-type
config>service>vpls>sap>stp
config>service>vpls>spoke-sdp>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the maximum number of bridges for STP behind this SAP.
If there is only a single bridge, transitioning to forwarding state is based on handshaking (fast transitions). If more than two bridges are connected via a shared media, their SAPs should all be configured as shared, and timer-based transitions are used.
The no form of this command reverts to the default value.
link-type pt-pt
mst-instance mst-inst-number
config>service>vpls>sap>stp
Supported on all 7210 SAS platforms as described in this document
This command configures Multiple Spanning Tree Instance (MSTI) related parameters at the SAP level. This context can be open only for existing MSTIs defined at the service level.
Specifies an existing MSTI number.
mst-path-cost inst-path-cost
no mst-path-cost
config>service>vpls>sap>stp>mst-instance
Supported on all 7210 SAS platforms as described in this document
This commands specifies path-cost within a specific instance. If a loop occurs, this parameter indicates the probability of a specific port being assigned a forwarding state. The highest value expresses the lowest priority.
By default, the path-cost is proportional to the link speed.
The no form of this command reverts to the default value.
Specifies the contribution of this port to the MSTI path cost.
mst-port-priority stp-priority
no mst-port-priority
config>service>vpls>sap>stp>mst-instance
Supported on all 7210 SAS platforms as described in this document
This command specifies the port priority within a specific instance. If a loop occurs, this parameter indicates the probability of a specific port being assigned a forwarding state.
The no form of this command reverts to the default value.
mst-port-priority 128
Specifies the value of the port priority field.
max-age seconds
no max-age
config>service>vpls>stp
config>template>vpls-template>stp
Supported on all 7210 SAS platforms as described in this document
This command configures how many hops a BPDU can traverse the network starting from the root bridge. The message age field in a BPDU transmitted by the root bridge is initialized to 0. Each other bridge takes the message_age value from BPDUs received on their root port and increments this value by 1. The message_age therefore reflects the distance from the root bridge. BPDUs with a message age exceeding the max-age value are ignored.
STP uses the max-age value configured in the root bridge. This value is propagated to the other bridges via the BPDUs.
The no form of this command reverts to the default value.
max-age 20
Specifies the max info age for the STP instance in seconds.
mode {rstp | comp-dot1w | dot1w | mstp | pmstp}
no mode
config>service>vpls>stp
Supported on all 7210 SAS platforms as described in this document
This command specifies the version of STP that the bridge is currently running.
See Spanning tree operating modes for information about these modes.
The no form of this command reverts to the default.
mode rstp
Keyword that corresponds to the Rapid STP specified in IEEE 802.1D/D4-2003.
Keyword that corresponds to the mode where the Rapid STP is backward compatible with IEEE 802.1w.
Keyword that corresponds to the Rapid STP fully conformant to IEEE 802.1w.
Keyword that sets MSTP as the STP mode of operation. Corresponds to the Multiple STP specified in 802.1Q REV/D5.0-09/2005
This mode is supported only in VPLS services where the mVPLS flag is configured.
[no] mst-instance mst-inst-number
config>service>vpls>stp
Supported on all 7210 SAS platforms as described in this document
This command configures Multiple Spanning Tree Instance (MSTI) related parameters. MSTP supports ‟16” instances. The instance ‟0” is mandatory (by protocol) and cannot be created by the CLI. The software automatically maintains this instance.
Specifies the MST instance.
mst-priority bridge-priority
no mst-priority
config>service>vpls>stp>mst-instance
Supported on all 7210 SAS platforms as described in this document
This command specifies the bridge priority for this specific Multiple Spanning Tree Instance for this service. The bridge-priority value reflects likelihood that the switch is chosen as the regional root switch (65535 represents the least likely). It is used as the highest 4 bits of the bridge ID included in the MSTP BPDUs generated by this bridge.
The values of the priority are only multiples of 4096 (4k). If a value is specified that is not a multiple of 4K, the value is replaced by the closest multiple of 4K (lower than the value entered).
All instances that are created by the vlan-range command do not have an explicit definition of bridge-priority and inherit the default value.
The no form of this command reverts to the default value.
mst-priority 32768
Specifies the priority of this specific MSTI for this service.
[no] vlan-range [vlan-range]
config>service>vpls>stp>mst-instance
Supported on all 7210 SAS platforms as described in this document
This command specifies a range of VLANs associated with a particular MSTI. This range applies to all SAPs of the mVPLS.
Every VLAN range that is not assigned within any of the created mst-instance is automatically assigned to mst-instance 0. This instance is automatically maintained by the software and cannot be modified. Changing the VLAN range value can be performed only when the specific mst-instance is shut down.
The no form of this command removes the vlan-range from the specific mst-instance.
The first VLAN range specifies the left-bound (minimum value) of a range of VLANs that are associated with the mVPLS SAP. This value must be smaller than (or equal to) the second VLAN range value. The second VLAN range specifies the right-bound (maximum value) of a range of VLANs that are associated with the mVPLS SAP.
mst-max-hops hops-count
no mst-max-hops
config>service>vpls>stp
Supported on all 7210 SAS platforms as described in this document
This command specifies the number of hops in the region before BPDU is discarded and the information held for the port is aged out. The root bridge of the instance sends a BPDU (or M-record) with remaining-hop-count set to configured max-hops. When a bridge receives the BPDU (or M-record), it decrements the received remaining-hop-count by 1 and propagates it in the BPDU (or M-record) it generates.
The no form of this command reverts the hops-count to the default value.
mst-max-hops 20
Specifies the maximum number of hops.
mst-name region-name
no mst-name
config>service>vpls>stp
Supported on all 7210 SAS platforms as described in this document
This command defines an MST region name. Two bridges are considered as a part of the same MST region as soon as their configuration of the MST region name, the MST-revision and VLAN-to-instance assignment is identical.
The no form of this command removes region-name from the configuration.
no mst-name
Specifies an MST-region name, up to 32 characters.
mst-revision revision-number
config>service>vpls>stp
Supported on all 7210 SAS platforms as described in this document
This command defines the MST configuration revision number. Two bridges are considered as a part of the same MST region if their configured MST-region name, MST-revision, and VLAN-to-instance are identical.
The no form of this command reverts to the default value.
mst-revision 0
Specifies the MSTP revision number to define the MSTP region.
path-cost sap-path-cost
no path-cost
config>service>vpls>sap>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the STP path cost for the SAP.
The path cost is used by STP to calculate the path cost to the root bridge. The path cost in BPDUs received on the root port is incremented with the configured path cost for that SAP. When BPDUs are sent out other egress SAPs, the newly calculated root path cost is used.
STP suggests that the path cost is defined as a function of the link bandwidth. Because SAPs are controlled by complex queuing dynamics in the STP, path cost is a static configuration.
The no form of this command reverts the path cost to the default value.
Specifies the path cost for the SAP.
[no] port-num virtual-port-number
config>service>vpls>sap>stp
config>service>vpls>spoke-sdp>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the virtual port number, which uniquely identifies a SAP within configuration BPDUs.
The internal representation of a SAP is unique to a system and has a reference space much bigger than the 12 bits definable in a configuration BPDU. STP takes the internal representation value of a SAP and identifies it using a virtual port number that is unique from every other SAP defined on the TLS. The virtual port number is assigned at the time that the SAP is added to the TLS. Because the order that the SAP was added to the TLS is not preserved between reboots of the system, the virtual port number may change between restarts of the STP instance.
The virtual port number cannot be administratively modified.
priority bridge-priority
no priority
config>service>vpls>stp
config>template>vpls-template>stp
Supported on all 7210 SAS platforms as described in this document
This command is used to populate the priority portion of the bridge ID field within outbound BPDUs (the most significant 4 bits of the bridge ID). It is also used as part of the decision process when determining the best BPDU between messages received and sent. All values are truncated to multiples of 4096, conforming with IEEE 802.1t and 802.1D-2004.
The no form of this command reverts the bridge priority to the default value.
priority 4096
Specifies the bridge priority for the STP instance.
priority stp-priority
no priority
config>service>vpls>spoke-sdp
config>service>vpls>sap>stp
Supported on all 7210 SAS platforms as described in this document
This command configures the STP priority for the SAP or spoke SDP.
When configuration BPDUs are received, the priority is used in some circumstances as a tie breaking mechanism to determine whether the SAP is designated or blocked.
In traditional STP implementations (802.1D-1998), this field is called the port priority and has a value of 0 to 255. This field is coupled with the port number (0 to 255 also) to create a 16-bit value. In the latest STP standard (802.1D-2004), only the upper 4 bits of the port priority field are used to encode the SAP priority. The remaining 4 bits are used to extend the port ID field into a 12-bit virtual port number field. The virtual port number uniquely references a SAP within the STP instance.
STP computes the actual priority by taking the input value and masking out the lower four bits. The result is the value that is stored in the priority parameter. For example, if a value of 0 is entered, masking out the lower 4 bits results in a parameter value of 0. If a value of 255 is entered, the result is 240.
The no form of this command reverts the STP priority to the default value.
priority 128
Specifies the STP priority value for the SAP or spoke SDP.