Technical Documentation



arp {aging-timer minutes;passive-learning;}

Hierarchy Level

[edit system]

Release Information

Statement introduced before JUNOS Release 7.4.

Statement introduced in JUNOS Release 9.0 for EX Series switches.


Specify ARP options. You can enable backup VRRP routers to learn ARP requests for VRRP-IP to VRRP-MAC address translation. You can also set the time interval between ARP updates.


aging-timer—Time interval in minutes between ARP updates. In environments where the number of ARP entries to update is high (for example, on routers only, metro Ethernet environments), increasing the time between updates can improve system performance.

passive-learning—Configures backup VRRP routers or switches to learn the ARP mappings (IP-to-MAC address) for hosts sending the requests. By default, the backup VRRP router drops these requests; therefore, if the master router fails, the backup router must learn all entries present in the ARP cache of the master router. Configuring passive learning reduces transition delay when the backup router is activated.

Default: 20 minutes
Range: 5 to 240 minutes

Required Privilege Level

system—To view this statement in the configuration.

system-control—To add this statement to the configuration.

Published: 2010-04-26