D-Link DGS-3312SR, Руководство по эксплуатации продукта

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DGS-3312SR Gigabit Layer 3 Switch
value is 125 .
Max Response Time This determines the maximum amount of time in seconds allowed before sending
an IGMP response report. The Max Response Time field allows an entry between
1
and 25 (seconds). The default value is 10 .
Robustness Variable Adjust this variable according to expected packet loss. If packet loss on the VLAN
is expected to be high, the Robustness Variable should be increased to
accommodate increased packet loss. This entry field allows an entry of
2 to 255 .
The default value is 2 .
Last Member Query
Interval Specifies the maximum amount of time between group-specific query messages,
including those sent in response to leave group messages. The default value is
1 .
Host Timeout This is the maximum amount of time in seconds allowed for a host to continue
membership in a multicast group without the Switch receiving a host membership
report. The default value is
260 .
Route Timeout This is the maximum amount of time in seconds a route is kept in the forwarding
table without receiving a membership report. The default value is
260 .
Leave Timer
This specifies the maximum amount of time in seconds between the Switch
receiving a leave group message from a host, and the Switch issuing a group
membership query. If no response to the membership query is received before the
Leave Timer expires, the (multicast) forwarding entry for that host is deleted.
Querier State Choose Enabled to enable transmitting IGMP Query packets. The default value is
Disabled .
State Select Enabled to implement IGMP Snooping. This is Disabled by default.
Static Router Ports
A static router port is a port that has a multicast router attached to it. Generally, this router would have a connection to a
WAN or to the Internet. Establishing a router port will allow multicast packets coming from the router to be propagated
through the network, as well as allowing multicast messages (IGMP) coming from the network to be propagated to the
router.
A router port has the following behavior:
•
All IGMP Report packets will be forwarded to the router port.
•
IGMP queries (from the router port) will be flooded to all ports.
•
All UDP multicast packets will be forwarded to the router port. Because routers do not send IGMP reports or
implement IGMP snooping, a multicast router connected to the router port of the Layer 3 Switch would not be
able to receive UDP data streams unless the UDP multicast packets were all forwarded to the router port.
A router port will be dynamically configured when IGMP query packets, RIPv2 multicast, DVMRP multicast, and PIM-
DM multicast packets are detected flowing into a port.
Open the IGMP folder and the click on the Static Router Ports Entry link to open the Current Static Router Ports
Entries window, as shown below.
Figure 4- 20. Current Static Router Port Entries window
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