SNR S2989G-48TX-DC — настройка IP-сервисов и DHCP: Руководство по конфигурации [199/553]

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S2989G-24TX Operation Manual

Chapter 3 IP services Configuration

3-37

failing manually.

Switch(config)#interface vlan 100

Switch(config-if-vlan100)#keepalive gateway 1.1.1.1 3 3

Switch(config-if-vlan100)#exit

Send ARP detection once 3 seconds to detect whether gateway A is reachable, after

3 times detection is failing, gateway A is considered to be unreachable.

3.13.4

Kepalive Gteway Troubleshooting

If there is any problem happens when using keepalive gateway function, please

check whether the problem is caused by the following reasons:

 Make sure the device is layer 3 switch, layer 2 switch does not support keepalive

gateway

 The detection method is used to point-to-point topology mode only

 Detect IPv4 accessibility by the method, so the detection result only affects IPv4

traffic, other traffic such as IPv6 is not affected

 Physical state of interface only controlled by physical signal

 Interface can’t run IPv4 after determine gateway is not reachable, so all relative

IPv4 routes are deleted and IPv4 route protocol can’t establish the neighbor on

the interface

3.14

DHCP

3.14.1

Introduction to DHCP

DHCP [RFC2131] is the acronym for Dynamic Host Configuration Protocol. It is a

protocol that assigns IP address dynamically from the address pool as well as other

network configuration parameters such as default gateway, DNS server, and default route

and host image file position within the network. DHCP is the enhanced version of BOOTP.

It is a mainstream technology that can not only provide boot information for diskless

workstations, but can also release the administrators from manual recording of IP

allocation and reduce user effort and cost on configuration. Another benefit of DHCP is it

can partially ease the pressure on IP demands, when the user of an IP leaves the network

that IP can be assigned to another user.

DHCP is a client-server protocol, the DHCP client requests the network address and

configuration parameters from the DHCP server; the server provides the network address

and configuration parameters for the clients; if DHCP server and clients are located in

different subnets, DHCP relay is required for DHCP packets to be transferred between the