R3204P16-HP Load Balancing Module Network Management Configuration Guide-6PW101

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To do… Use the command… Remarks
Configure the suppression time of
link-layer-state changes on the
Ethernet Interface
timer hold seconds
Optional
10 seconds by default
NOTE:
You can increase the pollin
g
interval to reduce network instability due to time delay or heavy con
g
estion.
Displaying and maintaining Ethernet interfaces
To do… Use the command… Remarks
Display the state of an
interface or subinterface and
the related information
display interface [ interface-type [ interface-number |
interface-number.subnumber ] ]
Available in any
view
Display the summary of an
interface or subinterface
display brief interface [ interface-type
[ interface-number | interface-number.subnumber ] ] [ |
{ begin | exclude | include } regular-expression ]
Available in any
view
Clear the statistics of an
interface or subinterface
reset counters interface [ interface-type
[ interface-number | interface-number.subnumber ] ]
Available in user
view
Configuring loopback and null interfaces
Configuring a loopback interface
A loopback interface is a software-only virtual interface. The physical layer state and link layer protocols
of a loopback interface are always up unless the loopback interface is manually shut down. A loopback
interface can be configured with an IP address. For the purpose of saving IP address resources, the IP
address is automatically configured with a 32-bit mask. Routing protocols can be enabled on a loopback
interface, and a loopback interface is capable of sending and receiving routing protocol packets.
Loopback interfaces are widely used. For example, you can configure a loopback interface address as
the source address of all the IP packets that the LB module generates. Because loopback interface
addresses are stable unicast addresses, they are usually used as device identifications. Therefore, when
you configure a rule on an authentication or security server to permit or deny packets generated by a
device, you can streamline the rule by configuring it to permit or deny packets carrying the loopback
interface address identifying the LB module. When you assign an IP address to a loopback interface for
source address binding, make sure that the route from the loopback interface to the peer is reachable. As
a result, all data packets sent to the loopback interface are considered as packets sent to the LB module
itself, so the module does not forward these packets.
Because a loopback interface is always up, it can be used for some other special purposes. For example,
if no router ID is configured for a dynamic routing protocol, the highest loopback interface IP address is
selected as the router ID. For another example, to avoid BGP sessions being interrupted by physical port
failure, you can use a loopback interface as the source interface of BGP packets. However, you must
ensure that the IP address of the loopback interface on the BGP peer is reachable. If EBGP connection is
involved, you need to allow the establishment of EBGP connections to non-directly-connected peers.
Follow these steps to configure a loopback interface: