Manual Chapter : 3-DNS Installation Guide v3.0: Additonal Setup Options

Applies To:

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3-DNS Controller versions 1.x - 4.x

  • 3.0 PTF-02, 3.0 PTF-01, 3.0.0
Manual Chapter


Additonal Setup Options

Enabling remote login tools

If you are setting up a crypto 3-DNS Controller that needs to communicate with non-crypto 3-DNS Controllers, you must enable the rsh and rcp tools on the crypto 3-DNS Controller. These are the standard communication and copying tools that non-crypto 3-DNS Controllers, BIG-IP Controllers, and EDGE-FX Caches use.

To enable the remote login tools on a crypto 3-DNS Controller

Run the rsetup script from the command line utility. The rsetup script performs several essential steps to enable access for rsh and rcp, and we strongly recommend that you use the script rather than doing this manually.

Preparing workstations for command line access

The type of system you have determines the options you have for remote command line administration:

  • Crypto 3-DNS Controllers support secure shell (SSH) command line access. If you have a Windows-based PC workstation, you can use the Mindbright Mindterm SSH console to run an ssh session. If you have a UNIX workstation, you can use the standard ssh client.
  • Non-crypto 3-DNS Controllers support command line access using a standard rsh shell.

If you are working with a crypto 3-DNS Controller, you can access a Mindbright Mindterm console through the web-based Configuration utility.

Addressing general networking issues

You must address several networking issues when you place a 3-DNS Controller in your network. These networking issues include routing, DNS configuration, and special email considerations. The type of hardware and software in your network determine how you address these issues. This section describes the following networking issues:

  • Using a serial terminal with the 3-DNS Controller
  • Configuring Sendmail

Using a serial terminal with the 3-DNS Controller

To configure a serial terminal in addition to the console

To configure a serial terminal, in addition to the standard console, for the 3-DNS Controller, you need to complete the following configuration steps. Note that if you are using a serial VT100 connection, you must edit both the /etc/ttys and bash_profile files on the 3-DNS Controller.

Note: Before you configure the serial terminal, you must disconnect the keyboard from the 3-DNS Controller. When there is no keyboard connected to the 3-DNS Controller, the 3-DNS Controller defaults to using the serial port for the console.

Before the 3-DNS Controller is booted, you must attach a serial device to the serial port in order for the controller to use the serial port as the console.

  1. Configure the serial terminal settings as follows:
    • 9600 baud
    • 8 bits
    • 1 stop bit
    • No parity
  2. Open the /etc/ttys file and find the line that reads ttyd0 off. Modify it as shown here:

    # PC COM ports (tty00 is DOS COM1) ttyd0 "/user/libexec/getty std.9600" vt100 on secure
  3. Save the /etc/ttys file and close it.
  4. Reboot the 3-DNS Controller.

Configuring Sendmail

You can configure the 3-DNS Controller to send email notifications to you, or to other administrators, using the Sendmail utility. The 3-DNS Controller includes a sample Sendmail configuration file that you can use to start with, but you must customize the Sendmail setup for your network environment before you can use it.

Before you begin setting up Sendmail, you may need to look up the name of the mail exchanger for your domain. If you already know the name of the mail exchanger, refer to Setting up Sendmail, on page 4-4 for details about setting up the sendmail daemon itself.

Finding the mail exchanger for your domain

You can use the nslookup command on any workstation that is configured for lookup. Once you find the primary IP address for your domain, you can find the mail exchanger for your domain.

To find the mail exchanger

  1. Identify the default server name for your domain. From a workstation capable of name resolution, type the following on the command line:


  2. The command returns a default server name and corresponding IP address:

    Default Server: <server name>
    Address: <server>

  3. Use the domain name to query for the mail exchanger:

    set q=mx
    <domain name>

The returned information includes the name of the mail exchanger. For example, the sample information shown in Figure 4.1 lists as the preferred mail exchanger.

Figure 4.1 Sample mail exchanger information   preference = 10, mail exchanger = nameserver = nameserver = internet address = internet address = internet address =

Setting up Sendmail

When you set up Sendmail, you must edit two configuration files. Since the 3-DNS Controller does not accept email messages, you can use the crontab utility to purge unsent or returned messages and send them to yourself or another administrator.

To set up and start Sendmail

  1. Copy /etc/ to /etc/
  2. To set the name of your mail exchange server, open the /etc/ file and set the DS variable to the name of your mail exchanger. The syntax for this entry is:


  3. Save and close the /etc/ file.
  4. To allow Sendmail to purge outgoing messages that cannot be delivered immediately from the queue containing mail, open the /etc/crontab file, and change the last line of the file to read:

    0,15,30,45 * * * * root /usr/sbin/sendmail -q > /dev/null 2>&1

  5. Save and close the /etc/crontab file.
  6. To prevent returned or undelivered email from going unnoticed, open the /etc/aliases file and create an entry so that root points to you or another administrator at your site.


  7. Save and close the /etc/aliases file.
  8. Run the newaliases command to generate a new aliases database that incorporates the information you added to the /etc/aliases file.
  9. To turn Sendmail on, either reboot the system or type the following command:

    /usr/sbin/sendmail -bd -q30m

Note: The 3-DNS Controller supports only outgoing mail for Sendmail servers.