Dell PowerConnect 5316M, Reference Manual

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SNMP Commands
231
• engineid-string — Specifies a character string that identifies the engine ID. (Range: 5 - 32
characters)
• default
— The engine ID is created automatically based on the device MAC address.
Default Setting
The engine ID is not configured.
If SNMPv3 is enabled using this command, and the default is specified, the default engine ID
is defined per standard as:
• First 4 octets — First bit = 1, the rest is IANA Enterprise number = 674.
• Fifth octet — Set to 3 to indicate the MAC address that follows.
• Last 6 octets — MAC address of the device.
Command Mode
Global Configuration mode
User Guidelines
• To use SNMPv3, you have to specify an engine ID for the device. You can specify your own ID
or use a default string that is generated using the MAC address of the device.
If the SNMPv3 engine ID is deleted or the configuration file is erased, SNMPv3 cannot be
used. By default, SNMPv1/v2 are enabled on the device. SNMPv3 is enabled only by defining
the Local Engine ID.
If you want to specify your own ID, you do not have to specify the entire 32-character engine
ID if it contains trailing zeros. Specify only the portion of the engine ID up to the point where
just zeros remain in the value. For example, to configure an engine ID of
123400000000000000000000, you can specify snmp-server engineID local 1234.
Since the engine ID should be unique within an administrative domain, the following is
recommended:
• For a standalone device, use the default keyword to configure the engine ID.
• For a stackable system, configure the engine ID and verify its uniqueness.
Changing the value of the engine ID has the following important side-effect. A user's
password (entered on the command line) is converted to an MD5 or SHA security digest. This
digest is based on both the password and the local engine ID. The user’s command line
password is then destroyed, as required by RFC 2274. As a result, the security digests of
SNMPv3 users become invalid if the local value of the engine ID change, and the users will
have to be reconfigured.
You cannot specify an engine ID that consists of all 0x0, all 0xF or 0x000000001.