SNR S2940-8G-v2, Configuration Manual

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SNR S2940-8G-v2 Switch Configuration Guide
Gratuitous ARP Configuration
2. Display configurations about gratuitous ARP
Command Explanation
Admin Mode and Configuration Mode
show ip gratuitous-arp [interface
vlan <1-4094>] To display configurations about gratuitous ARP.
33.3 Gratuitous ARP Configuration Example
Switch
PC1 PC4 PC2 PC3 PC5
Interface vlan 10
192.168.15.254/24
Interface vlan 1
192.168.14.254/24
Figure 33.1: Gratuitous ARP Configuration Example
For the network topology shown in the figure above, interface VLAN10 whose IP address
is 192.168.15.254 and network address mask is 255.255.255.0 in the switch system. Three
PCs - PC3, PC4, PC5 are connected to the interface. The IP address of interface VLAN 1 is
192.168.14.254, its network address mask is 255.255.255.0. Two PCs - PC1 and PC2 are con-
nected to this interface. Gratuitous ARP can be enabled through the following configuration:
1. Configure two interfaces to use gratuitous ARP at one time.
Switch(config)#ip gratuitous-arp 300
2. Configure gratuitous ARP specifically for only one interface at one time.
Switch(config)#interface vlan 10
Switch(Config-if-Vlan10)#ip gratuitous-arp 300
Switch(Config-if-Vlan10)#exit
33.4 Gratuitous ARP Troubleshooting
Gratuitous ARP is disabled by default. And when gratuitous ARP is enabled, the debugging infor-
mation about ARP packets can be retrieved through the command debug ARP send.
If gratuitous ARP is enabled in global configuration mode, it can be disabled only in global con-
figuration mode. If gratuitous ARP is configured in interface configuration mode, the configuration
can only be disabled in interface configuration mode.
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