snmpwalk: Decryption error for APC Rack PDU

I have an APC Rack PDU (AP7920) and have configured:

  • [x] Enable SNMPv3 access
  • Username: switch
  • Authentication Passphrase: test
  • Privacy Passphrase: test
  • Authentication Protocol: (o) MD5
  • Privacy Protocol: (o) DES
  • Access Control: [x] Enable, Username: switch, NMS IP/Host Name: 0.0.0.0

Now when I execute snmpwalk I get:

# snmpwalk -v3 -a MD5 -A test -u switch -x DES -X test 192.168.1.1
snmpwalk: Decryption error

What am I doing wrong?

My goal is to switch outlets via SNMP


Unfortunately I can't comment yet, so giving here my 2 cents:

  1. your snmpwalk command misses the option to specify the security level:

    -l LEVEL set security level (noAuthNoPriv|authNoPriv|authPriv)

since you specify both Authentication and Privacy, you might try again with:

# snmpwalk -v3 -a MD5 -A PqzRcPor1QPyBHRdVOjA -u switch -l authPriv -x DES -X PqzRcPor1QPyBHRdVOjA 192.168.1.1
  1. have you tried switching MD5/DES to something else like SHA/AES and see if you get something different ?

The above answer by Lex Li is correct too: APC specifies a password length should be no less than 12 chars.