Configuring Basic SNMPv2c Functions
Context
For the configuration of basic SNMP functions, steps 1, 4, 5, and 6 are mandatory. After the configuration is complete, the NMS and managed device can communicate with each other through SNMP.
The traps sent by the managed device do not need to be acknowledged by the NMS.
The informs sent by the managed device need to be acknowledged by the NMS. If no acknowledgement message is received from the NMS within a specified time period, the managed device resends the inform until the number of retransmissions reaches the maximum.
When sending an inform to the NMS, the managed device also records the inform in the log. If an inform is sent to the NMS when the NMS or the link between NMS and managed device is faulty, the NMS can still receive the inform after fault recovery.
Procedure
- Run system-view
The system view is displayed.
- (Optional) Run snmp-agent
The SNMP agent is enabled.
By default, the SNMP agent is disabled. Executing the snmp-agent command can enable the SNMP agent, even if no parameter is specified in the command.
- (Optional) Run snmp-agent udp-port port-num
The port number of the SNMP agent is changed.
The default port number of the SNMP agent is 161.
This command enhances device security. After this command is run on an SNMP agent connecting to the NMS, ensure that the port number on the NMS is the same as the changed port number. Otherwise, the SNMP agent cannot connect to the NMS.
- Run snmp-agent sys-info version v2c
The SNMP version is set to SNMPv2c.
By default, the device supports SNMPv3. If the SNMP version is set to SNMPv2c, the device supports both SNMPv2c and SNMPv3, and can be managed by NMSs running SNMPv2c and SNMPv3.
- Run snmp-agent community { read | write } { community-name | cipher community-name } [ mib-view view-name | acl { acl-number | acl-name } | alias alias-name ] *, snmp-agent community { read | write } [ cipher ] community-name [ mib-view view-name ] acl-ipv4 { acl-number | acl-name } [ acl-ipv6 { acl-number | acl-name } ] [ alias alias-name ] or snmp-agent community { read | write } [ cipher ] community-name [ mib-view view-name ] acl-ipv6 { acl-number | acl-name } [ alias alias-name ]
The community name is set.
By default, no community name exists on the device, and the device checks complexity of community names. If the check fails, the community name cannot be configured. To ensure the security of SNMP community names, you are advised to refrain from using the snmp-agent community complexity-check disable command to disable community name complexity check. The device has the following requirements for community name complexity:
The minimum length of a community name is determined by the set password min-length command. By default, a password contains 8 characters.
A community name includes at least two kinds of characters, which can be uppercase letters, lowercase letters, digits, and special characters (excluding question marks and spaces). When double quotation marks are used around the string, spaces are allowed in the string.
To change the access right of the NMS, see Restricting Management Rights of the NMS. Ensure that the community name of the NMS is the same as that set on the agent; otherwise, the NMS cannot access the agent.
- Choose one of the following commands according to your network requirements to configure a destination IP address of the traps and error codes sent from the device.
Before configuring a device to send traps, confirm that the information center has been enabled. The information center can be enabled by running the info-center enable command.
- When the managed device and NMS reside on an IPv4 network, configure the device to send either traps or informs to the NMS as follows:
To configure a destination IP address for the traps and error codes sent from the device, run the snmp-agent target-host trap address udp-domain ip-address [ udp-port port-number | source interface-type interface-number | [ public-net | vpn-instance vpn-instance-name ] ] * params securityname { security-name | cipher security-name } [ v2c | private-netmanager | notify-filter-profile profile-name | ext-vb ] * command.
To configure a destination IP address for the informs and error codes sent from the device, run the snmp-agent target-host inform address udp-domain ip-address [ udp-port port-number | source interface-type interface-number | [ vpn-instance vpn-instance-name | public-net ] ]* params securityname { security-name | cipher security-name } v2c [ notify-filter-profile profile-name | ext-vb ] * command.
When the managed device and NMS reside on an IPv6 network, run the snmp-agent target-host trap ipv6 address udp-domain ipv6-address [ udp-port port-number | vpn-instance vpn-instance-name ] * params securityname { security-name | cipher security-name } [ v2c | private-netmanager | notify-filter-profile profile-name | ext-vb ] * command to set the target host that receives traps and error codes.
An IPv6 network supports only traps, but does not support informs.
Note the following before running the command:The default destination UDP port number is 162. To ensure secure communication between the NMS and managed devices, change the UDP port number to a lesser-known port number by using the udp-port command.
The securityname parameter identifies the devices that send traps to the NMS.
If the NMS and managed device are both Huawei products, the private-netmanager parameter can be configured to add more information to trap messages to help you locate and solve problems more quickly. The additional information includes trap type, serial number, and sending time.
If traps sent from the managed device to the NMS need to be transmitted over a public network, the public-net parameter needs to be configured. If traps sent from the managed device to the NMS need to be transmitted over a private network, the vpn-instance vpn-instance-name parameter needs to be configured. This parameter is used to specify a VPN that will take over the transmission task.
- (Optional) Run snmp-agent sys-info { contact contact | location location }
The device administrator's contact information or location is configured.
By default, the device administrator's contact information is "R&D Beijing, Huawei Technologies Co., Ltd." and location is "Beijing China."
This step is required for the NMS administrator to view contact information and locations of the device administrator when the NMS manages many devices. This helps the NMS administrator to contact the device administrator for fault location and rectification.
- (Optional) Run snmp-agent packet max-size byte-count
The maximum size of an SNMP packet that the device can receive and send is set.
By default, the maximum size of an SNMP packet is 12000 bytes.
When the size of an SNMP packet is larger than the configured value, the device discards the SNMP packet. To ensure that the NMS can process SNMP packets properly, set the byte-count parameter to the maximum size of an SNMP packet that the NMS can process.
- (Optional) Run snmp-agent protocol source-interface interface-type interface-number
A source interface is configured for receiving and responding to NMS's requests.
By default, a source interface is randomly selected for receiving and responding to NMS's requests.
- (Optional) Run snmp-agent protocol ipv6 source-ip ipv6-address
A source IPv6 address is configured for receiving and responding to NMS's requests.
By default, a source IPv6 address is randomly selected for receiving and responding to NMS's requests.
- (Optional) Run snmp-agent protocol server [ ipv4 | ipv6 ] disable
The SNMP IPv4 or IPv6 listening port is disabled.
By default, the SNMP IPv4 or IPv6 listening port is disabled.
If ipv4 or ipv6 is not selected, both SNMP IPv4 and IPv6 listening ports are disabled.
If the managed device only needs to send traps to the NMS but does not need to perform Get/Set operation, SNMP port listening is not required. In this case, run this command so that SNMP no longer processes SNMP packets. Exercise caution when running this command.