• If the limit is decreased after it is reached, Dell Networking OS does not clear the existing sessions.
Entries are cleared after a timeout (you may also clear entries using
clear ip mroute
).
NOTE: Dell Networking OS waits at least 30 seconds between stopping and starting IGMP join
processing. You may experience this delay when manipulating the limit after it is reached.
When the multicast route limit is reached, Dell Networking OS displays the following:
3w1d13h: %RPM0-P:RP2 %PIM-3-PIM_TIB_LIMIT: PIM TIB limit reached. No new
routes will
be learnt until TIB level falls below low watermark.
3w1d13h: %RPM0-P:RP2 %PIM-3-PIM_TIB_LIMIT: PIM TIB below low watermark.
Route learning
will begin.
To limit the number of multicast routes, use the following command.
• Limit the total number of multicast routes on the system.
CONFIGURATION mode
ip multicast-limit
The range if from 1 to 16000.
The default is
4000
.
NOTE: The IN-L3-McastFib CAM partition is used to store multicast routes and is a separate
hardware limit that exists per port-pipe. Any software-configured limit may supersede by this
hardware space limitation. The opposite is also true, the CAM partition might not be exhausted at
the time the system-wide route limit the
ip multicast-limit
command sets is reached.
Preventing a Host from Joining a Group
You can prevent a host from joining a particular group by blocking specific IGMP reports. Create an
extended access list containing the permissible source-group pairs.
NOTE: For rules in IGMP access lists,
source
is the multicast source, not the source of the IGMP
packet. For IGMPv2, use the keyword
any
for
source
(as shown in the following example), because
IGMPv2 hosts do not know in advance who the source is for the group in which they are interested.
To apply the access list, use the following command.
• Apply the access list.
INTERFACE mode
ip igmp access-group
access-list-name
Dell Networking OS Behavior
: Do not enter the
ip igmp access-group
command before creating the
access-list. If you do, after entering your first deny rule, Dell Networking OS clears multicast routing table
and re-learns all groups, even those not covered by the rules in the access-list, because there is an
implicit
deny all
rule at the end of all access-lists. Therefore, configuring an IGMP join request filter in this
order might result in data loss. If you must enter the
ip igmp access-group
command before creating
the access-list, prevent Dell Networking OS from clearing the routing table by entering a
permit any
rule
with high sequence number before you enter any other rules.
In the following example, virtual local area network (VLAN) 400 is configured with an access list to permit
only IGMP reports for group 239.0.0.1. Though Receiver 2 sends a membership report for groups
239.0.0.1 and 239.0.0.2, a multicast routing table entry is created only for group 239.0.0.1. VLAN 300 has
Multicast Features
531
Summary of Contents for Z9000
Page 1: ...Dell Configuration Guide for the Z9000 System 9 7 0 0 ...
Page 80: ...grub reboot 80 Management ...
Page 128: ... 0 Te 1 1 Te 1 2 rx Flow N A N A 128 Access Control Lists ACLs ...
Page 491: ...Figure 70 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 491 ...
Page 496: ...Figure 73 MSDP Default Peer Scenario 1 496 Multicast Source Discovery Protocol MSDP ...
Page 497: ...Figure 74 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 497 ...
Page 498: ...Figure 75 MSDP Default Peer Scenario 3 498 Multicast Source Discovery Protocol MSDP ...
Page 760: ...Figure 100 Single and Double Tag TPID Match 760 Service Provider Bridging ...
Page 761: ...Figure 101 Single and Double Tag First byte TPID Match Service Provider Bridging 761 ...
