Allied Telesis AR400 manual When a client joins a group, Group List Entry timeout 225 secs Ports

Page 18

Multiple potential IGMP queriers > Explanation of Multiple potential IGMP queriers

When a client joins a group

Now imagine that Client 1 sends a Membership Report to switch 2 for the group

224.12.13.14. If we check the group membership for switch 2 by using the command show igmpsnooping, we see a group entry for 224.12.13.14.

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 225 secs
Ports 2

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

If we check the group membership for switches 1 and 3, we see no entries for 224.12.13.14, but see an All Groups entry on each switch. The All Groups entry points to the Querier, switch 2. The output for switch 1, for example, shows port 49 as the All Groups port, indicating that switch 1 reaches the Querier via port 49.

Manager Switch 1> 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	25 secs
Ports		None
All	Groups		Entry timeout	177 secs
Ports		49

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

Note: An All Groups port does not necessarily indicate that an IGMP Querier can be found via that port—it could be a router instead. See "Controlling which addresses create All Groups entries" on page 95 for more information.

Page 18 AlliedWare™ OS How To Note: IGMP

Image 18

Contents Contents IntroductionConfigurable Igmp timers and counters Query solicitation rapid recovery from topology changesHow clients leave groups queries and timers Example of bad choices for timer valuesProducts and software versions this note applies to Igmp feature Software versions Products 4 AlliedWare OS How To Note Igmp5 AlliedWare OS How To Note Igmp Igmp overviewQueriers and Snoopers 6 AlliedWare OS How To Note Igmp MessagesIP address, binary 7 AlliedWare OS How To Note IgmpChoosing group addresses MAC address, hex8 AlliedWare OS How To Note Igmp Avoid x.0.0.y, x.0.1.y, x.128.0.y, and x.128.1.y9 AlliedWare OS How To Note Igmp Igmp snoopingExample Configure switch 10 AlliedWare OS How To Note Igmp11 AlliedWare OS How To Note Igmp Explanation of Igmp snoopingGroup List Entry timeout 257 Secs Ports All Groups 235 Using Show command output to investigate Igmp stateGroup List Entry timeout 136 secs Ports None 12 AlliedWare OS How To Note Igmp13 AlliedWare OS How To Note Igmp Group Last AdvWhen a client leaves a group Group List Entry timeout 247 secs Ports14 AlliedWare OS How To Note Igmp 15 AlliedWare OS How To Note Igmp Multiple potential Igmp queriers16 AlliedWare OS How To Note Igmp When there are no group members Other Querier timeout .. secs17 AlliedWare OS How To Note Igmp All Groups Entry timeout Secs Ports When a client joins a groupGroup List Entry timeout 225 secs Ports 18 AlliedWare OS How To Note Igmp19 AlliedWare OS How To Note Igmp Group ListGroup List Last Adv 20 AlliedWare OS How To Note Igmp 21 AlliedWare OS How To Note Igmp Igmp proxySwitch 3 is an Igmp Proxy 22 AlliedWare OS How To Note Igmp23 AlliedWare OS How To Note Igmp Group List Entry timeout 122 secs Ports NoneAll Groups Entry timeout 145 Secs Ports Explanation of Igmp proxyGroup Entry timeout Secs Ports 24 AlliedWare OS How To Note IgmpGroup Entry timeout 182 secs Ports 25 AlliedWare OS How To Note IgmpQuery solicitation rapid recovery from topology changes 26 AlliedWare OS How To Note IgmpHow query solicitation works 27 AlliedWare OS How To Note Igmp Initial stateWhy convergence takes so long without query solicitation 28 AlliedWare OS How To Note IgmpExample Explanation from the perspective of switch 2, the snooper 29 AlliedWare OS How To Note IgmpAll Groups Entry timeout 236 secs Ports 30 AlliedWare OS How To Note Igmp31 AlliedWare OS How To Note Igmp Explanation from the perspective of switch 1, the querierGroup Entry timeout 18 secs Ports Shows this entryGroup Entry timeout 115 secs Ports 32 AlliedWare OS How To Note Igmp33 AlliedWare OS How To Note Igmp Speeding up Igmp convergence in a non-looped topology34 AlliedWare OS How To Note Igmp Switch 1 sends GQ35 AlliedWare OS How To Note Igmp Igmp filtering controlling multicast distributionTypes command Set switch port=1 igmpfilter=136 AlliedWare OS How To Note Igmp Switch 3 is also an Igmp Snooper 37 AlliedWare OS How To Note Igmp38 AlliedWare OS How To Note Igmp Received Passed Dropped39 AlliedWare OS How To Note Igmp No group memberships40 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 When we deny groups instead of replacing them Modify switch 2 Configuration46 AlliedWare OS How To Note Igmp Group 224.12.13.11 Entry timeout 255 secs Ports 224.12.13.12 47 AlliedWare OS How To Note Igmp48 AlliedWare OS How To Note Igmp Static IgmpSwitch 2 is an Igmp Snooper 49 AlliedWare OS How To Note Igmp50 AlliedWare OS How To Note Igmp Group Entry timeout Infinity Ports 51 AlliedWare OS How To Note IgmpExplanation of Static Igmp 52 AlliedWare OS How To Note Igmp When we add a static entry on another switchModify switch 3 Configuration MulticastPkts 675826All Groups Entry timeout 247 secs Ports 53 AlliedWare OS How To Note Igmp54 AlliedWare OS How To Note Igmp Group Entry timeout Infinity Ports 5,26 55 AlliedWare OS How To Note Igmp56 AlliedWare OS How To Note Igmp MulticastPkts 36350MulticastPkts 14756 When a static entry’s port goes down Group Entry timeout Infinity Ports None57 AlliedWare OS How To Note Igmp 58 AlliedWare OS How To Note Igmp How clients leave groups queries and timersQuerier timer values Overview of leave processSnooper timer values 59 AlliedWare OS How To Note IgmpConsequences for high-loss and high-lag networks Comparing the Querier and Snooper timers60 AlliedWare OS How To Note Igmp Describes the new behaviour61 AlliedWare OS How To Note Igmp Igmp fast leaveSwitch 1 is an Igmp Querier 62 AlliedWare OS How To Note Igmp63 AlliedWare OS How To Note Igmp Explanation of Igmp fast leave64 AlliedWare OS How To Note Igmp When fast leave is disabledGroup Entry timeout 2 secs Ports Fast Leave OffGroup Entry timeout Secs Ports None When you enable fast leave on switchIt is safe to ignore the group entry on switch 65 AlliedWare OS How To Note IgmpWhen you set fast leave on all interfaces 66 AlliedWare OS How To Note IgmpTo specify single mode, use either of the commands Multiple host mode for fast leaveTo specify multiple mode, use the command 67 AlliedWare OS How To Note Igmp68 AlliedWare OS How To Note Igmp Configurable Igmp timers and counters Timer and counter relationships69 AlliedWare OS How To Note Igmp 70 AlliedWare OS How To Note Igmp Initial configurationEach example modifies the following base configuration Software versions71 AlliedWare OS How To Note Igmp Last Member Query Count and Last Member Query Interval Default values72 AlliedWare OS How To Note Igmp What these counters do73 AlliedWare OS How To Note Igmp Potential problems with changing these countersHow to change these counters Last Member Query Interval 255 10secs74 AlliedWare OS How To Note Igmp Last Member Query CountRobustness Variable Potential problems with changing this counterHow to change this counter What this counter doesPotential problems with changing this timer Default Query IntervalWhat this timer does How to change this timer77 AlliedWare OS How To Note Igmp Query Response IntervalQuery Response Interval 100 10secs Default Timeout Interval Synchronisation of timers78 AlliedWare OS How To Note Igmp Default Timeout Interval = 2*130 + 100/10 = 270 seconds 79 AlliedWare OS How To Note Igmp80 AlliedWare OS How To Note Igmp Default Timeout Interval = 2*125 + 100/10 = 260 secondsDefault Timeout Interval 280 Secs Query Response Interval 200 10secsDefault Timeout Interval 180 Secs 81 AlliedWare OS How To Note IgmpDefault Query Interval 200 Secs Default Timeout Interval 410 82 AlliedWare OS How To Note IgmpCommands to configure these settings are Example of bad choices for timer valuesImagine the following changes to the configuration 83 AlliedWare OS How To Note IgmpProblem 3 Default Timeout Interval too short Problem 1 Last Member Query Interval too shortProblem 2 Query Response Interval short Last Member Query Interval was set to 5, using the commandFor more information, see Synchronisation of timers on 85 AlliedWare OS How To Note Igmp86 AlliedWare OS How To Note Igmp Stopping snoopers from snooping non-IGMP messages87 AlliedWare OS How To Note Igmp Router uses Ospf Configure the router88 AlliedWare OS How To Note Igmp Ports 2489 AlliedWare OS How To Note Igmp Ports 25Preventing an All Groups entry for a port Disabled All-groups Ports90 AlliedWare OS How To Note Igmp Disabling All Groups entry for a portEntry timeout 216 Secs Check the group entry timeout valuesReset port 24’s packet counters Enabling All Groups entry again92 AlliedWare OS How To Note Igmp Check the group entry timeout values againEntry timeout Secs MulticastPktsEnable Igmp debugging Entry timeout 259 Secs93 AlliedWare OS How To Note Igmp 94 AlliedWare OS How To Note Igmp MulticastPkts 91495 AlliedWare OS How To Note Igmp Controlling which addresses create All Groups entriesConfiguring switch 96 AlliedWare OS How To Note Igmp224.0.0.5 97 AlliedWare OS How To Note Igmp Configuring switches 1 98 AlliedWare OS How To Note IgmpAdding other router addresses Returning to the default list 99 AlliedWare OS How To Note Igmp224.0.0.254 Using the other routermode options 100 AlliedWare OS How To Note Igmp101 AlliedWare OS How To Note Igmp Statically specifying that a port is a router portCheck the current Igmp snooping entries Statically add port 6 as a router port attached to Vlan To remove the static configuration, simply delete it102 AlliedWare OS How To Note Igmp Stop port 6 from being a static router port103 AlliedWare OS How To Note Igmp Igmp debuggingClient joins a group Client leaves a group IgmpSnoopMembershipQuery setting timer at 2 secs for group104 AlliedWare OS How To Note Igmp Several minutes later the group entry times outPort entry times out Manager Switch 3 del vlan=100 port=5105 AlliedWare OS How To Note Igmp Snooped ports change106 AlliedWare OS How To Note Igmp Report is filtered outPort in the All Groups list is unplugged 107 AlliedWare OS How To Note Igmp Output for show ip igmp changesAppendix STP state Switch108 AlliedWare OS How To Note Igmp State Forwarding109 AlliedWare OS How To Note Igmp Manager Switch 3 show stp port=25-26