Getting error log of "snmpwalk: Authentication failure (incorrect password, community or key)" after RE switchover
e.g.
[engip@l-labsnmp01 ~]$ snmpwalk -v3 -l authPriv -u snmp-noc -a MD5 -A "xxxxx123" -x AES -X "xxxxx123" 10.116.250.103
snmpwalk: Authentication failure (incorrect password, community or key)
This is due to change of engine-id after RE switchover when used engine-id use-mac-address.
Recommended to use engine-id local or use-default-ip-address.
When no configured engine-id:
For QFX, "use-mac-address" is the default setting.
For the ACX/EX/PTX/MX, use-default-ip-address is the default setting.
After changed the config of engine-id , the usm user need to be reconfigured again.
Have a copy of snmp config.
Delete snmp config.
First configure local engine id:
set snmp engine-id local 80000a4c0432633463
commit
Then reconfigure snmp v3 usm
set snmp v3 usm local-engine user test1 authentication-md5 authentication-password xxxxx123
Configure rest of snmp config
commit.
https://www.juniper.net/documentation/us/en/software/junos/network-mgmt/topics/topic-map/configure-the-local-engine-id.html
For the engine ID, we recommend using the primary IP address of the device if the device has multiple routing engines and has the primary IP address configured. Alternatively, you can use the MAC address of the management port if the device has only one Routing Engine.
https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/engine-id-edit-snmp-qfx-series.html
For QFX series, when no snmp engine-id is configured, the default value for the configuration is use-mac-address.
snmp engine-id
use-mac-address
For ACX, EX, and MX series, when no snmp engine-id is configured, the default value for the configuration is use-default-ip-address.
use-default-ip-address
PR :1784543 - MX304 SNMPv3 password not working after 7-10 days not using.
AT#22.