ZyXEL Communications XS3800-28, Руководство пользователя, Страница: 498 / 789

Chapter 66 IGMP
XS3800-28 User’s Guide
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following screen.
Figure 395 DVMRP: Duplicate VID Error Message
66.4 Default DVMRP Timer Values
The following are some default DVMRP timer values.
66.5 Loopback Interface
The loopback interface is a virtual interface which can be assigned an IP address and used by routing
protocols. The loopback interface does not need to be connected to any devices and will always be
available if the Switch is functioning normally and connected to a network. You can enable multiple
loopback interfaces on the Switch, and each loopback interface must be uniquely identified.
The Switch can use a loopback interface address as the source address of all packets that originate
from the Switch. Filters can then be applied to the loopback address to protect the system.
Note: You have to first create a loopback interface and specify an interface ID in the SYSTEM
> Interface Setup screen.
Click NETWORKING > Loopback Interface > IPv4 Loopback Interface to display the following screen.
Table 260 DVMRP: Default Timer Values
DVMRP FIELD DEFAULT VALUE
Probe interval 10 sec
Report interval 35 sec
Route expiration time 140 sec
Prune lifetime Variable (less than 2 hours)
Prune retransmission time 3 sec with exponential back off
Graft retransmission time 5 sec with exponential back off