This section provides information to configure VPLS services using the command line interface.
Topics in this section include:
The following fields require specific input (there are no defaults) to configure a basic VPLS service:
The following example displays a configuration of a local VPLS service on ALU-1.
The following example displays a configuration of a distributed VPLS service between ALU-1, ALU-2, and ALU-3. The vc-id for all mesh SDPs must match the service-id.
This section provides a brief overview of the tasks that must be performed to configure both local and distributed VPLS services and provides the CLI commands.
For VPLS services:
Topics in this section include:
Use the following CLI syntax to create a VPLS service:
The following example displays a VPLS configuration:
Use the following CLI syntax to create a split horizon group for a VPLS instance. Including the residential-group parameter creates a residential split horizon group.
The following example displays a VPLS configuration:
The MAC move feature is useful to protect against undetected loops in the VPLS topology as well as the presence of duplicate MACs in a VPLS service. For example, if two clients in the VPLS have the same MAC address, the VPLS will experience a high relearn rate for the MAC and will shut down the SAP or spoke SDP when the threshold is exceeded. Use the following CLI syntax to configure MAC move parameters:
The following example displays a MAC move configuration:
Modifying some of the STP parameters allows the operator to balance STP between resiliency and speed of convergence extremes.
The following STP parameters can be modified at the VPLS level:
STP always uses the locally configured values for the first three parameters (Admin State, Mode and Priority).
For the parameters Hello Time and Hold Count, the locally configured values are only used when this bridge has been elected root bridge in the STP domain; otherwise, the values received from the root bridge are used. The exception to this rule is that Hello Time is always taken from the locally configured parameter.
The administrative state of STP at the VPLS level is controlled by the shutdown command.For SAPs, if STP on the VPLS is administratively disabled, any BPDUs are forwarded transparently through the 7705 SAR. If STP on the VPLS is administratively enabled, but the administrative state of a SAP is down, BPDUs received on such a SAP are discarded.
The 7705 SAR does not support BPDU extraction over spoke SDPs. If STP on the VPLS instance is disabled, BPDUs are forwarded transparently over the spoke SDP. If STP is enabled, the spoke SDP discards all BPDUs received.
The 7705 SAR operates in the Rapid Spanning Tree Protocol (RSTP) mode and is compliant with IEEE 802.1D-2004 - default mode.
The bridge-priority 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 will be truncated to multiples of 4096, conforming with IEEE 802.1t and 802.1D-2004.
The hello-time command configures the STP hello time for the VPLS STP instance.
The seconds 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.
On the 7705 SAR, the hello time for the spanning tree is determined by the locally configured parameter.
The hold-count command configures the peak number of BPDUs that can be transmitted in a period of one second.
A default QoS policy is applied to each ingress and egress SAP. Additional QoS policies can be configured in the config>qos context. There are no default filter policies. Filter policies are configured in the config>filter context and must be explicitly applied to a SAP.
For information on configuring ETH-CFM parameters on VPLS (Ethernet) SAPs, see ETH-CFM (802.1ag and Y.1731) Tasks.
Topics in this section include:
To configure a local VPLS service, enter the sap sap-id command twice with different port IDs in the same service configuration.
All supported service types and corresponding uplink SAPs are specified in the following examples.
The following example displays a local VPLS configuration:
To configure a distributed VPLS service, you must configure service entities on originating and far-end nodes. You must use the same service ID on all ends (for example, create a VPLS service ID 9000 on ALU-1, ALU-2, and ALU-3). A distributed VPLS consists of a SAP on each participating node and an SDP bound to each participating node.
For SDP configuration information, see Configuring SDPs. For SDP binding information, see Configuring SDP Bindings.
The following example displays a configuration of VPLS SAPs configured for ALU-1, ALU-2, and ALU-3:
When a VPLS has STP enabled, each SAP within the VPLS has STP enabled by default. The operation of STP on each SAP is governed by:
The administrative state of STP within a SAP controls how BPDUs are transmitted and handled when received. The allowable states are:
Note: The administratively down state allows a loop to form within the VPLS. |
The virtual port number 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 with its own virtual port number, which is unique to every other SAP defined on the VPLS. The virtual port number is assigned at the time that the SAP is added to the VPLS.
Since the order in which SAPs are added to the VPLS is not preserved between reboots of the system, the virtual port number may change between restarts of the STP instance. To achieve consistency after a reboot, the virtual port number can be specified explicitly.
SAP priority allows a configurable “tiebreaking” parameter to be associated with a SAP. When configuration BPDUs are being received, the configured SAP priority will be used in some circumstances to determine whether a SAP will be 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. See SAP Virtual Port Number for details on the virtual port number.
STP computes the actual SAP priority by taking the configured priority value and masking out the lower four bits. The result is the value that is stored in the SAP priority parameter. For example, if a value of 0 was entered, masking out the lower 4 bits would result in a parameter value of 0. If a value of 255 was entered, the result would be 240.
The default value for SAP priority is 128. This parameter can be modified within a range of 0 to 255, 0 being the highest priority. Masking causes the values actually stored and displayed to be 0 to 240, in increments of 16.
The SAP 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. Since SAPs are controlled by complex queuing dynamics, in the 7705 SAR the STP path cost is a purely static configuration.
The default value for SAP path cost is 10. This parameter can be modified within a range of 1 to 200000000, 1 being the lowest cost.
The SAP edge-port command is used to reduce the time it takes a SAP to reach the forwarding state when the SAP is on the edge of the network, and thus has no further STP bridge to handshake with.
The edge-port command is used to initialize the internal OPER_EDGE variable. At any time, when OPER_EDGE is false on a SAP, the normal mechanisms are used to transition to the forwarding state. When OPER_EDGE is true, STP assumes that the remote end agrees to transition to the forwarding state without actually receiving a BPDU with an agreement flag set.
The OPER_EDGE variable will dynamically be set to false if the SAP receives BPDUs (the configured edge-port value does not change). The OPER_EDGE variable will dynamically be set to true if auto-edge is enabled and STP concludes there is no bridge behind the SAP.
When STP on the SAP is administratively disabled and re-enabled, the OPER_EDGE is reinitialized to the value configured for edge-port.
Valid values for SAP edge-port are enabled and disabled with disabled being the default.
The SAP auto-edge command is used to instruct STP to dynamically decide whether the SAP is connected to another bridge.
If auto-edge is enabled, and STP concludes there is no bridge behind the SAP, the OPER_EDGE variable will dynamically be set to true. If auto-edge is enabled and a BPDU is received, the OPER_EDGE variable will dynamically be set to false (see SAP Edge Port).
Valid values for SAP auto-edge are enabled and disabled, with enabled being the default.
The SAP link-type parameter instructs STP on the maximum number of bridges behind this SAP.
If there is only a single bridge, transitioning to the forwarding state will be based on handshaking (fast transitions). If more than two bridges are connected by a shared media, their SAPs should all be configured as shared, and timer-based transitions are used.
Valid values for SAP link-type are shared and pt-pt, with pt-pt being the default.
The operational state of STP within a SAP controls how BPDUs are transmitted and handled when received. Defined states are:
Operationally disabled is the normal operational state for STP on a SAP in a VPLS that has any of the following conditions:
If the SAP enters the operationally up state with the STP administratively up and the SAP STP state is up, the SAP will transition to the STP SAP discarding state.
When, during normal operation, the router detects a downstream loop behind a SAP, BPDUs can be received at a very high rate. To recover from this situation, STP will transition the SAP to the disabled state for the forward-delay duration of 15 s.
A SAP in the discarding state only receives and sends BPDUs, building the local proper STP state for each SAP while not forwarding actual user traffic.
Note: In previous versions of the STP standard, the discarding state was called a blocked state. |
The learning state allows for the population of the MAC forwarding table before entering the forwarding state. In this state, no user traffic is forwarded.
Configuration BPDUs are sent out a SAP in the forwarding state. Layer 2 frames received on the SAP are source-learned and destination-forwarded according to the FIB. Layer 2 frames received on other forwarding interfaces and destined for the SAP are also forwarded.
To configure a VPLS service with a split horizon group, add the split-horizon-group parameter when creating the SAP. Traffic arriving on a SAP within a split horizon group will not be copied to other SAPs in the same split horizon group.
The following example displays a VPLS configuration with split horizon enabled:
This section contains the following topics:
VPLS provides scaling and operational advantages. A hierarchical configuration eliminates the need for a full mesh of VCs between participating devices. Hierarchy is achieved by enhancing the base VPLS core mesh of VCs with access VCs (spoke) to form two tiers. Spoke SDPs are generally created between Layer 2 switches and placed at the Multi-Tenant Unit (MTU). The PE routers are placed at the service provider's Point of Presence (POP). Signaling and replication overhead on all devices is considerably reduced.
A spoke SDP is treated like the equivalent of a traditional bridge port, where flooded traffic received on the spoke SDP is replicated on all other “ports” (other spoke and mesh SDPs or SAPs) and not transmitted on the port it was received on (unless a split horizon group was defined on the spoke SDP; see Configuring VPLS Spoke SDPs with Split Horizon).
A spoke SDP connects a VPLS service between two sites and, in its simplest form, could be a single tunnel LSP. A set of ingress and egress VC labels are exchanged for each VPLS service instance to be transported over this LSP. The PE routers at each end treat this as a virtual spoke connection for the VPLS service in the same way as the PE-MTU connections. This architecture minimizes the signaling overhead and avoids a full mesh of VCs and LSPs between the two metro networks.
A mesh SDP bound to a service is logically treated like a single bridge “port” for flooded traffic, where flooded traffic received on any mesh SDP on the service is replicated to other “ports” (spoke SDPs and SAPs) and not transmitted on any mesh SDPs.
A VC-ID can be specified with the SDP-ID. The VC-ID is used instead of a label to identify a virtual circuit. The VC-ID is significant between peer 7705 SAR routers on the same hierarchical level. The value of a VC-ID is conceptually independent from the value of the label or any other datalink-specific information of the VC.
Figure 100 displays an example of a distributed VPLS service configuration of spoke and mesh SDPs (unidirectional tunnels) between 7750 SR routers and 7705 SAR MTUs.
Use the following CLI syntax to create a mesh SDP binding with a distributed VPLS service. SDPs must be configured before binding. Refer to Configuring SDPs for information on creating SDPs. For information on configuring ETH-CFM parameters on VPLS (Ethernet) mesh SDPs, see ETH-CFM (802.1ag and Y.1731) Tasks.
Use the following CLI syntax to configure mesh SDP bindings:
Topics in this section include:
Use the following CLI syntax to create a spoke SDP binding with a distributed VPLS service. SDPs must be configured before binding. Refer to Configuring SDPs for information on creating SDPs. For information on configuring ETH-CFM parameters on VPLS (Ethernet) spoke SDPs, see ETH-CFM (802.1ag and Y.1731) Tasks.
Use the following CLI syntax to configure spoke SDP bindings:
The following displays SDP binding configurations for ALU-1, ALU-2, and ALU-3 for VPLS service ID 9000 for customer 6:
When a VPLS has STP enabled, each spoke SDP within the VPLS has STP enabled by default. The operation of STP on each spoke SDP is governed by:
The administrative state of STP within a spoke SDP controls how BPDUs are transmitted and handled when received. The allowable states are:
Note: The administratively down state allows a loop to form within the VPLS. |
The virtual port number uniquely identifies a spoke SDP within configuration BPDUs. The internal representation of a spoke SDP is unique to a system and has a reference space much larger than the 12 bits definable in a configuration BPDU. STP takes the internal representation value of a spoke SDP and identifies it with its own virtual port number, which is unique to any other spoke SDP defined on the VPLS. The virtual port number is assigned at the time that the spoke SDP is added to the VPLS.
Since the order in which spoke SDPs are added to the VPLS is not preserved between reboots of the system, the virtual port number may change between restarts of the STP instance. To achieve consistency after a reboot, the virtual port number can be specified explicitly.
Spoke SDP priority allows a configurable “tiebreaking” parameter to be associated with a spoke SDP. When configuration BPDUs are being received, the configured spoke SDP priority will be used in some circumstances to determine whether a spoke SDP will be 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 (also 0 to 255) 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 spoke SDP 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 spoke SDP within the STP instance. See Spoke SDP Virtual Port Number for details on the virtual port number.
STP computes the actual spoke SDP priority by taking the configured priority value and masking out the lower 4 bits. The result is the value that is stored in the spoke SDP priority parameter. For example, if a value of 0 was entered, masking out the lower 4 bits would result in a parameter value of 0. If a value of 255 was entered, the result would be 240.
The default value for spoke SDP priority is 128. This parameter can be configured within a range of 0 to 255, with 0 being the highest priority. Masking causes the values actually stored and displayed to be 0 to 240, in increments of 16.
The spoke SDP 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 spoke SDP. When BPDUs are sent out other egress spoke SDPs, the newly calculated root path cost is used.
STP suggests that the path cost is defined as a function of the link bandwidth. Since spoke SDPs are controlled by complex queuing dynamics, in the 7705 SAR the STP path cost is a purely static configuration.
The default value for spoke SDP path cost is 10. This parameter can be configured within a range of 1 to 200000000, with 1 being the lowest cost.
The spoke SDP edge-port command is used to reduce the time it takes a spoke SDP to reach the forwarding state when the spoke SDP is on the edge of the network and thus has no further STP bridge to handshake with.
The edge-port command is used to initialize the internal OPER_EDGE variable. At any time, when OPER_EDGE is false on a spoke SDP, the normal mechanisms are used to transition to the forwarding state. When OPER_EDGE is true, STP assumes that the remote end agrees to transition to the forwarding state without actually receiving a BPDU with an agreement flag set.
The OPER_EDGE variable will dynamically be set to false if the spoke SDP receives BPDUs (the configured edge-port value does not change). The OPER_EDGE variable will dynamically be set to true if auto-edge is enabled and STP concludes there is no bridge behind the spoke SDP.
When STP on the spoke SDP is administratively disabled and re-enabled, the OPER_EDGE is reinitialized to the value configured for edge-port.
Valid values for spoke SDP edge-port are enabled and disabled, with disabled being the default.
The spoke SDP auto-edge command is used to instruct STP to dynamically decide whether the spoke SDP is connected to another bridge.
If auto-edge is enabled, and STP concludes there is no bridge behind the spoke SDP, the OPER_EDGE variable will dynamically be set to true. If auto-edge is enabled and a BPDU is received, the OPER_EDGE variable will dynamically be set to false (see Spoke SDP Edge Port).
Valid values for spoke SDP auto-edge are enabled and disabled, with enabled being the default.
The spoke SDP link-type parameter instructs STP on the maximum number of bridges behind this spoke SDP.
If there is only a single bridge, transitioning to the forwarding state will be based on handshaking (fast transitions). If more than two bridges are connected by a shared media, their spoke SDPs should all be configured as shared, and timer-based transitions are used.
Valid values for spoke SDP link-type are shared and pt-pt, with pt-pt being the default.
To configure spoke SDPs with a split horizon group, add the split-horizon-group parameter when creating the spoke SDP. Traffic arriving on a SAP or spoke SDP within a split horizon group will not be copied to other SAPs or spoke SDPs in the same split horizon group.
The following example displays a VPLS configuration with split horizon enabled:
Use the following CLI syntax to enable selective MAC flush in a VPLS instance:
Use the following CLI syntax to disable selective MAC flush in a VPLS instance:
To establish routed VPLS (r-VPLS), a VPLS service must be bound to a standard IP interface within an IES or VPRN service. This is done by giving the VPLS a service-name and setting the VPLS allow-ip-int-binding flag. The binding is completed when the IES or VPRN interface is associated with the VPLS service-name. See Routed VPLS for details.
A VPLS service only supports binding for a single IP interface.
Additionally, an ingress IPv4 or IPv6 filter can be assigned to the VPLS SAP and the IES or VPRN interface. Use the v4- and v6-routed-override-filter commands to give the IP interface filter precedence over the VPLS SAP filter. See IES Command Reference and VPRN Services Command Reference for command descriptions.
Use the following CLI syntax to set up routed VPLS in a VPLS instance:
Use the following CLI syntax to bind an IES or VPRN interface to the routed VPLS instance and to configure an override filter:
Use the config>service>vpls>igmp-snooping or mld-snooping command to enable IP multicast in VPLS. The igmp-snooping and mld-snooping commands stop the default flooding of multicast traffic and allow the creation of a multicast forwarding database (MFIB) on a per-port basis.
The following displays a VPLS configuration with IGMP snooping. Configuring MLD snooping is similar except that the mld-snooping command and IPv6 addresses are used instead of the igmp-snooping command and IPv4 addresses:
Configuring IP multicast in a routed VPLS requires several steps.
Creating a Layer 2 multicast service in the context of an r-VPLS with PIM translation configured on the r-VPLS Layer 3 interface creates two multicast groups: one Layer 2 multicast group and one Layer 3 multicast group. Creating the Layer 2 multicast group automatically creates the Layer 3 group. It is not necessary to create both groups. The 7705 SAR uses one Layer 3 multicast group per source, and one Layer 2 multicast group per source per VPLS. See IP Multicast in r-VPLS for details.
Perform the following steps to create Layer 2 and Layer 3 multicast groups on a SAP or SDP.
The following displays illustrate step 1 to step 3 for an r-VPLS configuration with IGMP snooping. Configuring MLD snooping is similar except that the mld-snooping command and IPv6 addresses are used instead of the igmp-snooping command and IPv4 addresses.
To create the r-VPLS:
To link Layer 3 and Layer 2:
To configure PIM on a network interface:
The 7705 SAR supports multicast for VPLS and r-VPLS through IGMP and MLD snooping at the VPLS service level, as well as at the VPLS SAP and SDP (mesh and spoke) levels. Note the following considerations for IGMP and MLD snooping on a SAP or SDP.
Use the following CLI syntax to configure IGMP snooping parameters for VPLS and r-VPLS. Configuring MLD snooping parameters is similar except that the mld-snooping command and IPv6 addresses are used instead of the igmp-snooping command and IPv4 addresses.
The following displays IGMP snooping configuration for a VPLS service:
Use the following CLI syntax to configure IGMP snooping on a SAP. Configuring IGMP snooping on an SDP is similar. Configuring MLD snooping on a SAP or SDP is also similar, except that the mld-snooping command and IPv6 addresses are used instead of the igmp-snooping command and IPv4 addresses, and the max-num-grp-sources and max-num-sources commands do not apply.
The following displays IGMP snooping configuration for a VPLS service:
A static multicast group is not created until the source or starg—(*,G)—is specified. More than one group can be created per SAP or SDP, and more than one source can be added to a group. A static source cannot be added to a group if a starg already exists in the group.
Use the following CLI syntax to configure a static group for IGMP snooping on a VPLS SAP. Configuring a static group for IGMP snooping on an SDP is similar. Configuring a static group for MLD snooping on a SAP or SDP is also similar, except that the mld-snooping command and IPv6 addresses are used instead of the igmp-snooping command and IPv4 addresses.
The following displays a static group configuration for IGMP snooping on a VPLS SAP (multiple groups and multiple sources):
Use the pim-snooping command to connect a source in a Layer 2 access network to the host in a Layer 3 core network.
Use the following CLI syntax to configure PIM snooping for VPLS and to configure the maximum number of multicast groups for PIM snooping for VPLS SAPs and spoke SDPs.
The following displays a VPLS configuration with PIM snooping.
To configure firewall security functionality, you must:
The following example displays the security zone configuration output.
This section discusses the following service management tasks:
You can change existing service parameters. The changes are applied immediately.
To display a list of services, use the show service service-using vpls command. Enter the parameters, such as description, SAP, SDP, or service-MTU command syntax, then enter the new information.
The following displays a modified VPLS configuration:
To modify the range of VLANs on an access port that are to be managed by an existing management VPLS, first the new range should be entered and then the old range removed. If the old range is removed before a new range is defined, all customer VPLS services in the old range will become unprotected and may be disabled.
As with normal VPLS service, a management VPLS cannot be deleted until SAPs are unbound (deleted), interfaces are shut down, and the service is shut down on the service level.
Use the following CLI syntax to delete a management VPLS service:
You can shut down a management VPLS without deleting the service parameters.When a management VPLS is disabled, all associated user VPLS services are also disabled (to prevent loops). If this is not desired, first unmanage the user’s VPLS service by removing them from the managed-vlan-list.
A VPLS service cannot be deleted until SAPs and SDPs are unbound (deleted), interfaces are shut down, and the service is shut down on the service level.
Use the following CLI syntax to delete a VPLS service:
Use the following CLI syntax to shut down a VPLS service without deleting the service parameters:
To re-enable a VPLS service that was shut down: