Allied Telesis AR400 manual Enabling All Groups entry again, Check the group entry timeout values

Page 91

Stopping snoopers from snooping non-IGMP messages > Preventing an All Groups entry for a port

Enabling All Groups entry again

To further explore the system we will next reverse the process and follow switch 2 while group entries time out and the switch starts transmitting traffic for the group 224.12.13.14 to the router again. This sequence illustrates the time delay between when you change a port’s All Groups configuration and when multicast traffic flow changes.

1.Permit port 24 to be an All Groups port again.

Manager Switch 2> enable ip igmp allgroups=24

Info (1005003): Operation successful.

2.Check the group entry timeout values.

Manager Switch 2> show igmpsnooping

IGMP Snooping

------------------------------------------------------------------------

Status			Enabled
Disabled All-groups		ports	........ None
Vlan	Name (vlan id)	..... default (1)
Fast	Leave		Off
Group List
No	group memberships.
Vlan	Name (vlan id)	..... vlan100 (100)
Fast	Leave		Off


Group	List
Group. 224.12.13.14			Entry timeout	216	secs
Ports		None
All	Groups		Entry timeout	254	secs
Ports		24-25

------------------------------------------------------------------------

Port 24 is now an All Groups port. However, this not mean that it immediately starts receiving multicast packets for the group 224.12.13.14, as the next few steps show.

3.Reset port 24’s packet counters.

Manager Switch 2> reset switch port=24 counter

Info (1087003): Operation successful.

Page 91 AlliedWare™ OS How To Note: IGMP

Image 91

Contents Introduction ContentsExample of bad choices for timer values Query solicitation rapid recovery from topology changesHow clients leave groups queries and timers Configurable Igmp timers and countersProducts and software versions this note applies to 4 AlliedWare OS How To Note Igmp Igmp feature Software versions ProductsIgmp overview 5 AlliedWare OS How To Note IgmpQueriers and Snoopers Messages 6 AlliedWare OS How To Note IgmpMAC address, hex 7 AlliedWare OS How To Note IgmpChoosing group addresses IP address, binaryAvoid x.0.0.y, x.0.1.y, x.128.0.y, and x.128.1.y 8 AlliedWare OS How To Note IgmpIgmp snooping 9 AlliedWare OS How To Note IgmpExample 10 AlliedWare OS How To Note Igmp Configure switchExplanation of Igmp snooping 11 AlliedWare OS How To Note Igmp12 AlliedWare OS How To Note Igmp Using Show command output to investigate Igmp stateGroup List Entry timeout 136 secs Ports None Group List Entry timeout 257 Secs Ports All Groups 235Group Last Adv 13 AlliedWare OS How To Note IgmpGroup List Entry timeout 247 secs Ports When a client leaves a group14 AlliedWare OS How To Note Igmp Multiple potential Igmp queriers 15 AlliedWare OS How To Note Igmp16 AlliedWare OS How To Note Igmp Other Querier timeout .. secs When there are no group members17 AlliedWare OS How To Note Igmp 18 AlliedWare OS How To Note Igmp When a client joins a groupGroup List Entry timeout 225 secs Ports All Groups Entry timeout Secs PortsGroup List 19 AlliedWare OS How To Note IgmpGroup List Last Adv 20 AlliedWare OS How To Note Igmp Igmp proxy 21 AlliedWare OS How To Note Igmp22 AlliedWare OS How To Note Igmp Switch 3 is an Igmp ProxyExplanation of Igmp proxy Group List Entry timeout 122 secs Ports NoneAll Groups Entry timeout 145 Secs Ports 23 AlliedWare OS How To Note Igmp24 AlliedWare OS How To Note Igmp Group Entry timeout Secs Ports25 AlliedWare OS How To Note Igmp Group Entry timeout 182 secs Ports26 AlliedWare OS How To Note Igmp Query solicitation rapid recovery from topology changesHow query solicitation works Initial state 27 AlliedWare OS How To Note Igmp28 AlliedWare OS How To Note Igmp Why convergence takes so long without query solicitationExample 29 AlliedWare OS How To Note Igmp Explanation from the perspective of switch 2, the snooper30 AlliedWare OS How To Note Igmp All Groups Entry timeout 236 secs PortsShows this entry Explanation from the perspective of switch 1, the querierGroup Entry timeout 18 secs Ports 31 AlliedWare OS How To Note Igmp32 AlliedWare OS How To Note Igmp Group Entry timeout 115 secs PortsSpeeding up Igmp convergence in a non-looped topology 33 AlliedWare OS How To Note IgmpSwitch 1 sends GQ 34 AlliedWare OS How To Note IgmpIgmp filtering controlling multicast distribution 35 AlliedWare OS How To Note IgmpSet switch port=1 igmpfilter=1 Types command36 AlliedWare OS How To Note Igmp 37 AlliedWare OS How To Note Igmp Switch 3 is also an Igmp SnooperReceived Passed Dropped 38 AlliedWare OS How To Note IgmpNo group memberships 39 AlliedWare OS How To Note Igmp40 AlliedWare OS How To Note Igmp 41 AlliedWare OS How To Note Igmp 42 AlliedWare OS How To Note Igmp 43 AlliedWare OS How To Note Igmp 44 AlliedWare OS How To Note Igmp 45 AlliedWare OS How To Note Igmp Modify switch 2 Configuration When we deny groups instead of replacing them46 AlliedWare OS How To Note Igmp 47 AlliedWare OS How To Note Igmp Group 224.12.13.11 Entry timeout 255 secs Ports 224.12.13.12Static Igmp 48 AlliedWare OS How To Note Igmp49 AlliedWare OS How To Note Igmp Switch 2 is an Igmp Snooper50 AlliedWare OS How To Note Igmp 51 AlliedWare OS How To Note Igmp Group Entry timeout Infinity PortsExplanation of Static Igmp MulticastPkts 675826 When we add a static entry on another switchModify switch 3 Configuration 52 AlliedWare OS How To Note Igmp53 AlliedWare OS How To Note Igmp All Groups Entry timeout 247 secs Ports54 AlliedWare OS How To Note Igmp 55 AlliedWare OS How To Note Igmp Group Entry timeout Infinity Ports 5,26MulticastPkts 36350 56 AlliedWare OS How To Note IgmpMulticastPkts 14756 Group Entry timeout Infinity Ports None When a static entry’s port goes down57 AlliedWare OS How To Note Igmp Overview of leave process How clients leave groups queries and timersQuerier timer values 58 AlliedWare OS How To Note Igmp59 AlliedWare OS How To Note Igmp Snooper timer valuesDescribes the new behaviour Comparing the Querier and Snooper timers60 AlliedWare OS How To Note Igmp Consequences for high-loss and high-lag networksIgmp fast leave 61 AlliedWare OS How To Note Igmp62 AlliedWare OS How To Note Igmp Switch 1 is an Igmp QuerierExplanation of Igmp fast leave 63 AlliedWare OS How To Note IgmpFast Leave Off When fast leave is disabledGroup Entry timeout 2 secs Ports 64 AlliedWare OS How To Note Igmp65 AlliedWare OS How To Note Igmp When you enable fast leave on switchIt is safe to ignore the group entry on switch Group Entry timeout Secs Ports None66 AlliedWare OS How To Note Igmp When you set fast leave on all interfaces67 AlliedWare OS How To Note Igmp Multiple host mode for fast leaveTo specify multiple mode, use the command To specify single mode, use either of the commands68 AlliedWare OS How To Note Igmp Timer and counter relationships Configurable Igmp timers and counters69 AlliedWare OS How To Note Igmp Software versions Initial configurationEach example modifies the following base configuration 70 AlliedWare OS How To Note Igmp71 AlliedWare OS How To Note Igmp What these counters do Default values72 AlliedWare OS How To Note Igmp Last Member Query Count and Last Member Query IntervalLast Member Query Interval 255 10secs Potential problems with changing these countersHow to change these counters 73 AlliedWare OS How To Note IgmpLast Member Query Count 74 AlliedWare OS How To Note IgmpWhat this counter does Potential problems with changing this counterHow to change this counter Robustness VariableHow to change this timer Default Query IntervalWhat this timer does Potential problems with changing this timerQuery Response Interval 77 AlliedWare OS How To Note IgmpQuery Response Interval 100 10secs Synchronisation of timers Default Timeout Interval78 AlliedWare OS How To Note Igmp 79 AlliedWare OS How To Note Igmp Default Timeout Interval = 2*130 + 100/10 = 270 secondsQuery Response Interval 200 10secs Default Timeout Interval = 2*125 + 100/10 = 260 secondsDefault Timeout Interval 280 Secs 80 AlliedWare OS How To Note Igmp81 AlliedWare OS How To Note Igmp Default Timeout Interval 180 Secs82 AlliedWare OS How To Note Igmp Default Query Interval 200 Secs Default Timeout Interval 41083 AlliedWare OS How To Note Igmp Example of bad choices for timer valuesImagine the following changes to the configuration Commands to configure these settings areLast Member Query Interval was set to 5, using the command Problem 1 Last Member Query Interval too shortProblem 2 Query Response Interval short Problem 3 Default Timeout Interval too short85 AlliedWare OS How To Note Igmp For more information, see Synchronisation of timers onStopping snoopers from snooping non-IGMP messages 86 AlliedWare OS How To Note Igmp87 AlliedWare OS How To Note Igmp Ports 24 Configure the router88 AlliedWare OS How To Note Igmp Router uses OspfPorts 25 89 AlliedWare OS How To Note IgmpDisabling All Groups entry for a port Disabled All-groups Ports90 AlliedWare OS How To Note Igmp Preventing an All Groups entry for a portEnabling All Groups entry again Check the group entry timeout valuesReset port 24’s packet counters Entry timeout 216 SecsMulticastPkts Check the group entry timeout values againEntry timeout Secs 92 AlliedWare OS How To Note IgmpEntry timeout 259 Secs Enable Igmp debugging93 AlliedWare OS How To Note Igmp MulticastPkts 914 94 AlliedWare OS How To Note IgmpControlling which addresses create All Groups entries 95 AlliedWare OS How To Note Igmp96 AlliedWare OS How To Note Igmp Configuring switch224.0.0.5 97 AlliedWare OS How To Note Igmp 98 AlliedWare OS How To Note Igmp Configuring switches 1Adding other router addresses 99 AlliedWare OS How To Note Igmp Returning to the default list224.0.0.254 100 AlliedWare OS How To Note Igmp Using the other routermode optionsStatically specifying that a port is a router port 101 AlliedWare OS How To Note IgmpCheck the current Igmp snooping entries Stop port 6 from being a static router port To remove the static configuration, simply delete it102 AlliedWare OS How To Note Igmp Statically add port 6 as a router port attached to VlanIgmp debugging 103 AlliedWare OS How To Note IgmpClient joins a group Several minutes later the group entry times out IgmpSnoopMembershipQuery setting timer at 2 secs for group104 AlliedWare OS How To Note Igmp Client leaves a groupSnooped ports change Manager Switch 3 del vlan=100 port=5105 AlliedWare OS How To Note Igmp Port entry times outReport is filtered out 106 AlliedWare OS How To Note IgmpPort in the All Groups list is unplugged Output for show ip igmp changes 107 AlliedWare OS How To Note IgmpState Forwarding Switch108 AlliedWare OS How To Note Igmp Appendix STP state109 AlliedWare OS How To Note Igmp Manager Switch 3 show stp port=25-26