The main idea is to be bale to manage a number of nodes via SNMP wrtie community. This could be very valuable when such SNMP write community has been configured on the network devices and ACL is not allowing access to the device via SSH, TELNET, HTTP/S.
It could also help when a wrong/mistaken/inappropriate ACL is applied to the network devices, thus rejecting the follow-up access to these devices via the ordinary remote access protocols.
