SNMPv3 settings

defSecurityName STRING

defines the default security name to use for SNMPv3 requests. This can be overridden using the -u option.

defSecurityLevel noAuthNoPriv|authNoPriv|authPriv

defines the default security level to use for SNMPv3 requests. This can be overridden using the -l option.

If not specified, the default value for this token is noAuthNoPriv.

authPriv is only available if the software has been compiled to use the OpenSSL libraries.

defPassphrase STRING
defAuthPassphrase STRING
defPrivPassphrase STRING

define the default authentication and privacy passphrases to use for SNMPv3 requests. These can be overridden using the -A and -X options respectively.

The defPassphrase value will be used for the authentication and/or privacy passphrases if either of the other directives are not specified.

defAuthType MD5|SHA|SHA256
defPrivType DES|AES

define the default authentication and privacy protocols to use for SNMPv3 requests. These can be overridden using the -a and -x options respectively.

If not specified, SNMPv3 requests will default to MD5 authentication and DES encryption.

If the software has not been compiled to use the OpenSSL libraries, then only MD5 authentication is supported. Neither SHA authentication nor any form of encryption will be available.

defContext STRING

defines the default context to use for SNMPv3 requests. This can be overridden using the -n option.

If not specified, the default value for this token is the default context (i.e. the empty string "").

defSecurityModel STRING

defines the security model to use for SNMPv3 requests. The default value is usm, which is the only widely used security model for SNMPv3.

defAuthMasterKey 0xHEXSTRING
defPrivMasterKey 0xHEXSTRING
defAuthLocalizedKey 0xHEXSTRING
defPrivLocalizedKey 0xHEXSTRING

define the (hexadecimal) keys to be used for SNMPv3 secure communications.

SNMPv3 keys are frequently derived from a passphrase, as discussed in the defPassphrase section above. However for improved security a truly random key can be generated and used instead (which would normally has better entropy than a password unless it is amazingly long). The directives are equivalent to the short-form command line options -3m, -3M, -3k, and -3K.

Localized keys are master keys which have been converted to a unique key which is only suitable for on particular SNMP engine (agent). The length of the key needs to be appropriate for the authentication or encryption type being used:

auth keys: MD5=16 bytes, SHA1=20 bytes;
priv keys: DES=16bytes (8 bytes of which is used as an IV and not a key), and AES=16 bytes.