Managing System Services

System services include DNS, firewall, NDMP, and NTP. You can enable and configure these services by using the system service commands.

Managing DNS

The system service dns commands enable you to manage DNS.

Enabling and Configuring DNS

To enable and configure DNS on a node, use the system service dns modify command. You can use the command to modify the following settings:

  • List of domains

  • DNS name server or servers

  • Whether DNS is enabled or disabled

  • DNS timeout value, in seconds

  • Maximum number of DNS connection attempts

The following example modifies the DNS configuration on a node named node8 to use the domains lab.eng.example.com, eng.example.com, and example.com. The node uses three DNS name servers that have the IP addresses 10.1.14.1, 10.1.15.1, and 10.1.100.1. DNS is enabled. The timeout value for DNS requests is five (5) seconds; the maximum number of retries is two (2).

node::> system service dns modify -node node9
-domains lab.eng.example.com,eng.example.com,example.com -ns1 10.1.14.1
-ns2 10.1.15.1 -ns3 10.1.100.1 -state enabled -timeout 5 -attempts 2
Displaying Information about DNS Configurations

To display information about the DNS configuration for one or more nodes, use the system service dns show command. The command displays the following information:

  • Node name

  • Whether DNS is enabled or disabled

  • List of domains

  • List of name servers

  • Primary, secondary, and tertiary name servers (detailed view)

  • DNS timeout value, in seconds (detailed view)

  • Maximum number of DNS connection attempts (detailed view)

The following example displays the DNS configuration for both nodes in a two-node cluster:

node::> system service dns show
Node            State    Domains (first is ours)
node8           enabled  lab.eng.example.com, eng.example.com, example.com
   NameServers: 10.1.14.1 10.1.15.1 10.1.100.1
node9           enabled  lab.eng.example.com, eng.example.com, example.com
   NameServers: 10.1.14.1 10.1.15.1 -
Managing the Hosts Table

To manage the DNS hosts table, use the system service dns hosts commands. The hosts table is cluster wide, so you do not need to specify a node name with these commands.

Adding a Server to the Hosts Table

To add a server to the hosts table, use the system service dns hosts new command. When you add a server to the hosts table, you specify the host's IP address; you can optionally specify the host name and one or more aliases.

The following example adds a server with the IP address 10.98.48.14 and the name cleese.example.com to the hosts table. The server has an alias named wanda.example.com.

node::> system service dns hosts new -address 10.98.48.14
-hostname cleese.example.com
Displaying the Hosts Table

To display the hosts table, use the system service dns hosts show command. The command displays the following information about entries in the hosts table:

  • Server IP address

  • Host name, if any

  • Aliases, if any

The following example displays the hosts table:

node::> system service dns hosts show
Address        Hostname                     Aliases
10.98.48.14    cleese.example.com	    wanda.example.com
10.98.48.15    gilliam.example.com          brazil.example.com,
                                            monkeys.example.com
10.98.48.16    palin.example.com
10.98.48.17    idle.example.com
Modifying an Entry in the Hosts Table

To modify the attributes of a server that is listed in the hosts table, use the system service dns hosts modify command. You can change a server's host name, aliases, or both.

The following example adds an alias named travels.example.com to the server that has the IP address 10.98.48.16:

node::> system service dns hosts modify -address 10.98.48.16
-aliases travels.example.com
node::> system service dns hosts show
Address        Hostname                     Aliases
10.98.48.14    cleese.example.com	    wanda.example.com
10.98.48.15    gilliam.example.com          brazil.example.com,
                                            monkeys.example.com
10.98.48.16    palin.example.com	    travels.example.com
10.98.48.17    idle.example.com
Deleting an Entry from the Hosts Table

To delete a server from the hosts table, use the system service dns hosts delete command and specify the IP address of the server whose entry is to be deleted. The following example deletes a server that has the IP address 10.98.48.17 from the hosts table:

node::> system service dns hosts delete -address 10.98.48.17
node::> system service dns hosts show
Address        Hostname                     Aliases
10.98.48.14    cleese.example.com	    wanda.example.com
10.98.48.15    gilliam.example.com          brazil.example.com,
                                            monkeys.example.com
10.98.48.16    palin.example.com	    travels.example.com

Managing the Firewall Service

Use the system service firewall commands to enable, configure, and display information about firewall service for a node.

Enabling and Configuring the Firewall Service

To enable or disable firewall service and firewall logging on a node, use the system service firewall modify command. The following example turns on firewall service and logging for a node named node03:

node::> system service firewall modify -node node03 -enabled true
-logging true

Displaying Firewall Configuration

To display information about firewall service on one or more nodes, use the system service firewall show command, as shown in the following example:

node::> system service firewall show
Node          Enabled Logging
node01        true    false
node02        true    true
node03        true    true
node04        true    false

Managing NDMP

The system service ndmp commands enable you to manage NDMP service on nodes.

Enabling and Configuring NDMP

Use the system service ndmp modify command to enable or disable NDMP, to specify the NDMP user's ID and password, and to specify whether the NDMP user's password can be sent in clear text.

The following example enables NDMP on a node named node07. The NDMP user ID is tape1 and its password is tapedrive. The password cannot be sent in clear text.

node::> system service ndmp modify -node node07 -enable true
-clear-text false -user-id tape1 -password tapedrive

Displaying NDMP Configuration Information

The system service ndmp show command displays NDMP configuration information, as shown in the following example:

node::> system service ndmp show
Node                 Enabled   Clear text  User Id   Password

node04               true      true        ndmp      ndmp
node05               true      true        ndmp      ndmp
node06               true      false       tape1     tapedrive
node07               true      false       tape1     tapedrive

Managing NTP

The system service ntp commands enable you to manage NTP service.

Enabling NTP

Use the system service ntp config modify command to enable or disable the use of NTP in a cluster. The following example enables NTP in the cluster:

node::> system service ntp config modify -enabled true

Displaying NTP Status

The system service ntp config show command displays whether NTP is enabled in a cluster, as in the following example:

node::> system service ntp config show

                   NTP Enabled: true

Associating a Node with an NTP Server

Although NTP service is enabled or disabled for a cluster as a whole, you can associate individual nodes with one or more NTP servers by using the system service ntp server new command. When you run the command, you specify the node name and the NTP server's name or IP address; you can optionally specify whether the NTP server is the node's preferred NTP server (at the advanced privilege level or higher) and the version of NTP that the server is running.

The following example associates a node named node01 with an NTP server named ntp.example.com. The NTP server is the preferred server for the node, and the server runs NTP version 4.

node::> set -privilege advanced

Warning: These advanced commands are potentially dangerous; use them only when
         directed to do so by Network Appliance personnel.
Do you wish to continue? (y or n): y

node::*> system service ntp server new -node node01
server ntp.example.com -preferred true -version 4

Modifying the Attributes of an NTP Server

You can modify a node's association with an NTP server by using the system service ntp server modify command. Specifically, you can use the command to specify the version of NTP running on the server; at the advanced privilege level or higher, you can specify whether the server is the node's preferred NTP server.

The following example specifies the version of NTP as max (the highest available version) on an NTP server named ntp.example.com that is associated with a node named node01:

node::> system service ntp server modify -node node01
-server ntp.example.com -version max

Displaying Information about NTP Servers

To display information about NTP servers associated with nodes, use the system service ntp server show command. The command displays the following information:

  • Node name

  • NTP server name or IP address

  • Version of NTP running on the NTP server

  • Whether the NTP server is the node's preferred NTP server (advanced privilege level or higher only)

The following example displays information about NTP servers associated with nodes:

system service ntp show
Node   Server                         Version
-----------------------------------------------------------------------
node01
       ntp.example.com                max
node02
       ntp.example.com                max
       alt-ntp.example.com            4

Dissociating a Node from an NTP Server

To dissociate a node from an NTP server, use the system service ntp server delete command. The following example dissociates a node named node02 from an NTP server named alt-ntp.example.com:

node::> system service ntp server delete -node node02
-server alt-ntp.example.com