detach <iface>

Close an open interface previously attached. To clean up the configuration, all IP routing table entries referring to this interface are deleted, and forwarding references by any other interface to this interface are removed.

Because of certain design limitations, an interface should be detached only while it is idle, otherwise there is a (small) risk that an invalid interface pointer could be used to modify memory resulting in a crash (under UNIX) or low-memory-address corruption under MSDOS. For example, a packet may have to be retransmitted after an ack-timeout, but if the interface no longer exists Jnos gets confused...

Nither the encap nor the loopback interfaces can be successfully detached. However, beginning in Jnos 1.11e, a detach of the encap interface does result in all associated routes being deleted. To aid those gateway systems needing to update their encapped routes periodically: detach encap, then issue the new route commands.