Command Reference Guide

28 ● checkzero 3Com Router 5000 Family and Router 6000 Family
Command Reference
checkzero
Purpose Use the checkzero command to check the zero field of RIP-1 packet.
Use the undo checkzero command to cancel the check of the zero fields.
Syntax checkzero
undo checkzero
Parameters None
Default By default, RIP-1 performs the zero field check.
Example Configure not to perform zero check for RIP-1 packet.
[3Com -rip] undo checkzero
View This command can be used in the following views:
■ RIP view
Description According to the protocol (RFC1058) specifications, some fields in RIP-1 packets must
be zero, called zero fields. With the checkzero command, the zero check operation
for RIP-1 packet can be enabled or disabled. During the zero check operation, if the
RIP-1 packet in which the zero fields are not zeros is received, it will be rejected.
This command is ineffective to RIP-2 since RIP-2 packets have no zero fields.