1. Oracle Exadata Database Machine Getting Started Guide
  2. Post-Discovery Configuration and Verification

4 Post-Discovery Configuration and Verification

Once the Oracle Exadata Database Machine has been discovered through Enterprise Manager Cloud Control 13c, complete the following post-discovery verification:

Additionally, verify that all the components of Exadata Database Machine are discovered, up, and running. Also, ensure that the components are placed in the rack slots.

It is recommended that you review the logs to verify the successful completion of the discovery process. For the list of logs that you can review and their locations, see Review Logs.

If you encounter issues during discovery, then to troubleshoot them, see Discovery Troubleshooting and EMCLI Discovery Issues in the troubleshooting section.

Verify SNMP Subscription of the Oracle Management Agent to Exadata Storage Server

Exadata Storage Server SNMP configuration is performed using the cellcli command and can be run in batch using dcli from a compute node.

Note:

  • During the discovery process, you can optionally provide the necessary root credentials to subscribe for SNMP traps from Exadata Storage Servers. If you have done so, then you can skip the remaining steps of this section and proceed with Verify SNMP Configuration for InfiniBand Switch Targets.

  • While the public string is used for the SNMP examples in the following sections, it is supported to use any valid SNMP community string.

  • Use SNMP V3 subscriptions for IPv6-based Exadata Storage Server targets because of limitations in the SNMP V1 protocol.

  • The SNMP receivelet listens on a single address and port for all monitored targets. The port is the UDP port with the same number as the TCP port used in the EMD_URL.

    By default, the SNMP receivelet listens on all addresses; if the property SnmpRecvletListenNIC is set in the emd.properties file, the receivelet will attempt to resolve the value as either a name or IP address, and listen on only that address.

    This parameter is independent of AgentListenOnAllNICs and EMD_URL because in some installations, the Agent may need to communicate with the OMS and with managed targets on different networks.

Using the ALTER CELL Command

While using the ALTER CELL command, all existing subscribers must be specified along with the new subscriber being added. Any existing subscribers not specified will be removed from the configuration. Similarly, you can also modify the notificationPolicy or notificationMethod attributes.

While using the ALTER CELL command, the host= and community= attribute values should be quoted, and type= is NOT quoted.

If you are using the DCLI utility to set up SNMP configuration, then any command containing punctuation, which will be interpreted by the local shell, must be enclosed with double quotation marks. If the command includes the following characters, then outer quotation marks and escape characters are required:

  • $ (dollar sign)
  • ' (quotation mark)
  • < (less than)
  • > (greater than)
  • ( ) (parentheses)

The backslash (\) is the escape character that allows the characters to be passed to the cellcli utility without being interpreted by the remote shell.

Exadata Storage Server supports SNMP v1/v2 and v3 version based alert notifications to the subscribers. To receive alerts in the SNMPv3 version, the monitoring agents must be added to the snmpsubscriber list using a snmpuser.

cellcli command to create a snmpuser: 

# alter cell snmpuser = ((name=XXXXXX, authprotocol=sha, authpassword=*, privprotocol=AES, privpassword=*));

In the above command:

  • name: User name
  • Use only * for the password values in the command.
  • authProtocol: Authentication protocol. The supported protocol is SHA. The authProtocol must be specified for the snmpuser attribute. The system prompts for the authentication password. The authentication password must have 8 to 12 alphanumeric characters.
  • privProtocol: Encryption protocol. The protocol options are none, AES, or DES. When the privProtocol attribute is not specified, the default value is none . The system prompts for an encryption password if the encryption protocol is specified. The password is exactly 8 alphanumeric characters, and they are case sensitive.

cellcli command to subscribe the monitoring agents for receiving SNMPv1 alert notifications: 

# alter cell snmpsubscriber=((host=<Agent_Host>,port=<Agent_Port>,community=****))

cellcli command to subscribe the monitoring agents for receiving SNMPv3 alert notifications: 

# alter cell snmpsubscriber=((host=<Agent_Host>,port=<Agent_Port>, snmpUser=XXXXXXX, type=v3))

In the above two commands:

  • Agent_Host: Exadata Storage Server monitoring agent installed host
  • Agent_Port: Exadata Storage Server monitoring agent port
  • snmpUser is the one that is created using snmpuser attribute on Exadata Storage Server.

Check Current SNMP Configuration

Check the current SNMP configuration using the following cellcli commands:

  1. To list the current subscribers for SNMP:
    # cellcli -e list cell attributes snmpSubscriber

    When correctly configured, this command should list the primary and backup agents for the Exadata Storage Server target, for example:

    # cellcli -e "list cell attributes snmpSubscriber"
((host=[hostname.mycompany.com],port=3872,community=public),
(host=[hostname2.mycompany.com],port=3872,type=v3, snmpuser=v3user))

    If the required monitoring agents are not added to the SNMP subscribers list, then add the subscription. See Set Up SNMP Subscription for Exadata Storage Servers.

  2. To list the currently configured notification methods:
    # cellcli -e list cell attributes notificationMethod

    The possible values of the notificationMethod attribute are snmp, mail, none, or a combination of snmp and mail. Specify the combination as notificationMethod='mail,snmp'. The default value of the attribute is mail. For example, when the configuration is set for a combination of snmp and mail, then the command returns the following response: 

    # cellcli -e list cell attributes notificationMethod
snmp,mail
  3. To list the currently configured notification policy for SNMP:
    # cellcli -e list cell attributes notificationPolicy

    Possible values are any or all of Critical, Warning, and Clear. When correctly configured, this command should return Critical, Warning, Clear, for example: 

    # cellcli -e list cell attributes notificationPolicy
Critical,Warning,Clear

If SNMP configuration is not available, then configure it. See SNMP Configuration Missing in the troubleshooting section.

Configure SNMP Values Using dcli (optional)

The SNMP configuration commands can be run using dcli to perform the configuration in batch on all Exadata Storage Servers:

  1. Set the snmpSubscriber value:
    $ dcli -g cell_group -l root "cellcli -e \"alter cell snmpSubscriber=((host='[host name]',port=[port]),(host='[host name]',port=[port]))\""

    Where [host name] and [port] values are Agents monitoring your Exadata Storage Server targets.

  2. Set the notificationMethod value:
    $ dcli -g cell_group -l root "cellcli -e \"alter cell notificationMethod='snmp,mail'\""
  3. Set the notificationPolicy value:
    $ dcli -g cell_group -l root "cellcli -e \"alter cell notificationPolicy='Critical,Warning,Clear'\""

Verify SSH Connectivity Using cellcli

To begin monitoring using cellcli, open a new terminal and verify whether the SSH connectivity was successfully established: 

$ ssh -l cellmonitor <cell_ipaddress> cellcli -e 'list cell detail'

  • If you are not prompted for any password, then you can assume that the connectivity is established.

  • If you are asked to confirm whether you want to continue connecting, specify Yes.

Remove a Subscription

To remove the subscription, use the ALTER CELL command again by excluding the host name that you want to remove from the snmpsubscriber list.

Verify SNMP Configuration for InfiniBand Switch Targets

The SNMP configuration for Enterprise Manager monitoring of InfiniBand Switches is done automatically as part of the Enterprise Manager guided discovery process. It is good practice, however, to verify that SNMP configuration has been successful.

Note:

  • During the discovery process, you can optionally provide the necessary root credentials to set up SNMP trap for the InfiniBand Switch. If you have done so, then you can skip the remaining steps of this section.

  • ilom-admin is the preferred user when discovering an InfiniBand Switch target for full monitoring. root user can also be used for full monitoring. If the switch is discovered using root or ilom-admin user, the community string provided during discovery is added to the switch, if it doesn't exist already.

  • During SNMP V3 discovery, the V3 user added by the (discovery) user during discovery is added to the switch if the discovery is performed using root or the ilom-admin user.

To verify the InfiniBand Switch SNMP configuration for Enterprise Manager monitoring:

snmpget -v 1 -c <community_string> <hostname_of_IB_switch> 1.3.6.1.4.1.42.2.70.101.1.1.9.1.1.5

For example:

$ snmpget -v 1 -c public my_IB_switch.my_company.com 1.3.6.1.4.1.42.2.70.101.1.1.9.1.1.5
SNMPv2-SMI::enterprises.42.2.70.101.1.1.9.1.1.5 = INTEGER: 1

Note:

If the Timeout message is displayed as output for the above command, then it means that the InfiniBand Switch is not yet configured for SNMP. To configure SNMPv3 user and SNMP community, see Create an SNMPv3 User in IB Switches and Create SNMP Community for InfiniBand Switch Targets in the prerequisites section.

Note:

To remove the subscription, follow steps 1 to 5 in Create SNMP Community for InfiniBand Switch Targets (step 3 is not needed). In step 5, set the Agent compute node host name to 0.0.0.0 and the port to 0.

Verify the Cisco Ethernet Switch SNMP Configuration

Run the snmpwalk command line utility or equivalent tool to verify the Cisco Switch configuration.

Run the following commands to fetch and display the data from the Cisco switch:

$ snmpget –v 1 –c <community_string> <hostname_of_cisco_switch> 1.3.6.1.4.1.9.2.1.56.0
$ snmpget –v 2c –c <community_string> <hostname_of_cisco_switch> 1.3.6.1.4.1.9.2.1.56.0

Note:

If a timeout message is displayed as an output for the above command, then it means that the Cisco Switch is not yet configured correctly.

If the Cisco Ethernet Switch SNMP configuration is missing, then see Set Up SNMP Subscription for Cisco Ethernet Switch Targets in the troubleshooting section.

Verify the PDU SNMP Configuration

Use the snmpwalk command line utility or equivalent tool to verify the PDU configuration.

Run the following command to fetch and display the data from PDU:

snmpget –v 1 –c <community_string> <hostname_of_pdu> 1.3.6.1.4.1.2769.1.2.3.1.1.1.0

Note:

If a timeout message is displayed as an output for the above command, then it means that the PDU is not yet configured correctly.

If the PDU SNMP configuration is missing, then see Set Up SNMP for Power Distribution Unit (PDU) Targets in the troubleshooting section.