SNMPVACM(1) | Net-SNMP | SNMPVACM(1) |
snmpvacm - creates and maintains SNMPv3 View-based Access Control entries on a network entity
snmpvacm [COMMON OPTIONS] AGENT createSec2Group
MODEL SECURITYNAME GROUPNAME
snmpvacm [COMMON OPTIONS] AGENT deleteSec2Group MODEL
SECURITYNAME
snmpvacm [COMMON OPTIONS] AGENT createView [-Ce] NAME SUBTREE
MASK
snmpvacm [COMMON OPTIONS] AGENT deleteView NAME SUBTREE
snmpvacm [COMMON OPTIONS] AGENT createAccess GROUPNAME
[CONTEXTPREFIX] MODEL LEVEL CONTEXTMATCH READVIEW WRITEVIEW NOTIFYVIEW
snmpvacm [COMMON OPTIONS] AGENT deleteAccess GROUPNAME
[CONTEXTPREFIX] MODEL LEVEL
snmpvacm [COMMON OPTIONS] AGENT createAuth GROUPNAME
[CONTEXTPREFIX] MODEL LEVEL AUTHTYPE CONTEXTMATCH VIEW
snmpvacm [COMMON OPTIONS] AGENT deleteAuth GROUPNAME
[CONTEXTPREFIX] MODEL LEVEL AUTHTYPE
snmpvacm is an SNMP application that can be used to do simple maintenance on the View-based Control Module (VACM) tables of an SNMP agent. The SNMPv3 VACM specifications (see RFC2575) define assorted tables to specify groups of users, MIB views, and authorised access settings. These snmpvacm commands effectively create or delete rows in the appropriate one of these tables, and match the equivalent configure directives which are documented in the snmpd.conf(5) man page.
A fuller explanation of how these operate can be found in the project FAQ.
Create an entry in the SNMPv3 security name to group table. This table allows a single access control entry to be applied to a number of users (or 'principals'), and is indexed by the security model and security name values.
MODEL
SECURITYNAME
GROUPNAME
Delete an entry from the SNMPv3 security name to group table, thus removing access control settings for the given principal. The entry to be removed is indexed by the MODEL and SECURITYNAME values, which should match those used in the corresponding createSec2Group command (or equivalent).
Create an entry in the SNMPv3 MIB view table. A MIB view consists of a family of view subtrees which may be individually included in or (occasionally) excluded from the view. Each view subtree is defined by a combination of an OID subtree together with a bit string mask. The view table is indexed by the view name and subtree OID values.
[-Ce]
NAME
SUBTREE
MASK
Delete an entry from the SNMPv3 view table, thus removing the subtree from the given MIB view. Removing the final (or only) subtree will result in the deletion of the view. The entry to be removed is indexed by the NAME and SUBTREE values, which should match those used in the corresponding createView command (or equivalent).
When removing subtrees from a mixed view (i.e. containing both included and excluded subtrees), the included subtrees should be removed first.
Create an entry in the SNMPv3 access table, thus allowing a certain level of access to particular MIB views for the principals in the specified group (given suitable security model and levels in the request). The access table is indexed by the group name, context prefix, security model and security level values.
GROUPNAME
CONTEXTPREFIX
MODEL
LEVEL
CONTEXTMATCH
READVIEW
WRITEVIEW
NOTIFYVIEW
Delete an entry from the SNMPv3 access table, thus removing the specified access control settings. The entry to be removed is indexed by the group name, context prefix, security model and security level values, which should match those used in the corresponding createAccess command (or equivalent).
Create an entry in the Net-SNMP extension to the standard access table, thus allowing a certain type of access to the MIB view for the principals in the specified group. The interpretation of GROUPNAME, CONTEXTPREFIX, MODEL, LEVEL and CONTEXTMATCH are the same as for the createAccess directive. The extension access table is indexed by the group name, context prefix, security model, security level and authtype values.
AUTHTYPE
VIEW
Delete an entry from the extension access table, thus removing the specified access control settings. The entry to be removed is indexed by the group name, context prefix, security model, security level and authtype values, which should match those used in the corresponding createAuth command (or equivalent).
Note that snmpget REQUIRES an argument specifying the agent to query as described in the .I snmpcmd(1) manual page.
Given a pre-existing user dave (which could be set up using the snmpusm(1) command), we could configure full read-write access to the whole OID tree using the commands:
This creates a new security group named "RWGroup" containing the SNMPv3 user "dave", a new view "all" containing the full OID tree based on .iso(1) , and then allows those users in the group "RWGroup" (i.e. "dave") both read- and write-access to the view "all" (i.e. the full OID tree) when using authenticated SNMPv3 requests.
As a second example, we could set up read-only access to a portion of the OID tree using the commands:
This creates a new security group named "ROGroup" containing the (pre-existing) user "wes", a new view "sysView" containing just the OID tree based on .iso(1).org(3).dod(6).inet(1).mgmt(2).mib-2(1).system(1) , and then allows those users in the group "ROGroup" (i.e. "wes") read-access, but not write-access to the view "sysView" (i.e. the system group).
The following exit values are returned:
0 - Successful completion
1 - A usage syntax error (which displays a suitable usage message) or a request timeout.
2 - An error occurred while executing the command (which also displays a suitable error message).
This utility does not support the configuration of new community strings, so is only of use for setting up new access control for SNMPv3 requests. It can be used to amend the access settings for existing community strings, but not to set up new ones.
The use of numeric parameters for secLevel and contextMatch parameters is less than intuitive. These commands do not provide the full flexibility of the equivalent config file directives.
There is (currently) no equivalent to the one-shot configure directives rouser and rwuser.
snmpcmd(1), snmpusm(1), snmpd.conf(5), snmp.conf(5), RFC 2575, Net-SNMP project FAQ
05 Sep 2006 | V5.7.3 |