Variable Definitions

The following table defines parameters for the router vrf command.

Variable

Value

WORD<1–16>

Specifies the name of the VRF.

The following table defines parameters for the interface vlan command.

Variable

Value

<1-4059>

Specifies the VLAN ID in the range of 1 to 4059. By default, VLAN IDs 1 to 4059 are configurable and the system reserves VLAN IDs 4060 to 4094 for internal use. On switches that support the vrf-scaling and spbm-config-mode boot configuration flags, if you enable these flags, the system also reserves VLAN IDs 3500 to 3998. VLAN ID 1 is the default VLAN and you cannot create or delete VLAN ID 1.

The following table defines parameters for the GigabitEthernet command.

Variable

Value

GigabitEthernet{slot/port[/sub-port] [-slot/port[/sub-port]] [,...]}

Identifies the slot and port in one of the following formats: a single slot and port (slot/port), a range of slots and ports (slot/port-slot/port), or a series of slots and ports (slot/port,slot/port,slot/port). If the platform supports channelization and the port is channelized, you must also specify the sub-port in the format slot/port/sub-port.

The following table defines parameters for the ip igmp command.

Variable

Value

access-list WORD<1–64> {A.B.C.D/X} <eny-tx|deny-rx|deny-both|allow-only-tx|allow-only-rx|allow-only-both>

Specifies the name of the access list from 1–64 characters.

Creates an access control group entry for a specific IGMP interface. Specify the IP address of the host and the subnet mask used to determine the host or hosts covered by this configuration. You can use the host subnet mask to restrict access to a portion of the network for the host.

Indicates the action for the specified IGMP interface. For example, if you specify deny-both, the interface denies both transmitted and received traffic.

compatibility-mode

Activates v2-v3 compatibility mode. The default value is disabled, which means IGMPv3 is not compatible with IGMPv2. To use the default configuration, use the default option in the command:

default ip igmp compatibility-mode

, or use the no option to disable compatibility mode:

no ip igmp compatibility-mode

dynamic-downgrade-version

Configures if the system downgrades the version of IGMP to handle older query messages. If the system downgrades, the host with IGMPv3 only capability does not work. If you do not configure the system to downgrade the version of IGMP, the system logs a warning. The system downgrades to the oldest version of IGMP on the network by default. To use the default configuration, use the default option in the command:

default ip igmp dynamic-downgrade-version

or use the no option to disable downgrade:

no ip igmp dynamic-downgrade-version

igmpv3-explicit-host-tracking

Enables explicit host tracking on IGMPv3. The default state is disabled.

immediate-leave

Enables fast leave on a VLAN.

immediate-leave-members {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]}

Configures IGMP fast leave members on a VLAN to specify fast-leave-capable ports.

last-member-query-interval <0–255>

Configures the maximum response time (in tenths of a second) inserted into group-specific queries sent in response to leave group messages. This value is also the time between group-specific query messages. You cannot configure this value for IGMPv1.

Decreasing the value reduces the time to detect the loss of the last member of a group. The default is 10 tenths of a second. Configure this value between 3–10 (equal to 0.3 – 1.0 seconds).

mrdisc [maxadvertinterval <2–180>] [maxinitadvertinterval <2–180>] [maxinitadvertisements <2–15>] [minadvertinterval <3–180>] [neighdeadinterval <2–180>]

Configure the multicast router discovery options to enable the automatic discovery of multicast capable routers. The default parameter values are:

  • maxadvertinterval: 20 seconds

  • maxinitadvertinterval: 2 seconds

  • maxinitadvertisements: 3

  • minadvertinterval: 15 seconds

  • neighdeadinterval: 60 seconds

mrouter {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]}

Adds multicast router ports.

proxy

Activates the proxy-snoop option globally for the VLAN.

query-interval <1–65535>

Configures the frequency (in seconds) at which the VLAN transmits host query packets. The default value is 125 seconds.

query-max-response <0–255>

Configures the maximum response time (in tenths of a second) advertised in IGMPv2 general queries on this interface. You cannot configure this value for IGMPv1. Smaller values enable a router to prune groups faster. The default is 100 tenths of a second (equal to 10 seconds).

Important:

You must configure this value lower than the query-interval.

robust-value <2–255>

Configures the expected packet loss of a network. The default value is 2 seconds. Increase the value if you expect the network to experience packet loss.

router-alert

Instructs the router to ignore IGMP packets that do not contain the router alert IP option. When disabled (default configuration), the router processes IGMP packets regardless of the status of the router alert IP option.

Important:

To maximize network performance, configure this parameter according to the version of IGMP currently in use:

  • IGMPv1—Disable

  • IGMPv2—Enable

  • IGMPv3—Enable

snoop-querier

Enables the IGMP Layer 2 Querier feature on the VLAN. The default is disabled.

snoop-querier-addr {A.B.C.D}

Specifies the IGMP Layer 2 Querier source IP address.

snooping

Activates the snoop option for the VLAN.

ssm-snoop

Activates support for SSM on the snoop interface.

static-group {A.B.C.D} {A.B.C.D} [port] {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]}[static|blocked]

Configures IGMP static members to add members to a snoop group.

{A.B.C.D} {A.B.C.D} indicates the IP address range of the selected multicast group.

[port] {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]} adds ports to a static group entry.

[static|blocked] configures the route to static or blocked.

stream-limit stream-limit-max-streams <0-65535>

Configures multicast stream limitation on a VLAN to limit the number of concurrent multicast streams on the VLAN. The default is 4.

stream-limit-group {slot/port[/sub-port] [-slot/port[/sub-port]] [,...]} enable max-streams <0-65535>

Configures multicast stream limitation members on ports of a specific VLAN to limit the number of multicast groups that can join a VLAN. The default max-streams value is 4.

version <1–3>

Configures the version of IGMP that you want to configure on this interface. For IGMP to function correctly, all routers on a LAN must use the same version. The default value is 2 (IGMPv2).