Chapter 4. Configuring the GPT

4.1 Setting up the Routerboard

4.1.1 Terminal login

When connecting to the device using a terminal emulator, a login message will appear. The default username is admin. The password is normally set to rootme at the factory but may have been left unset (blank).

4.1.2 Setting the administration password

• Enter the following command to change the login password:

  /password

  Follow the on-screen prompts to complete the procedure.

4.1.3 Setting parameters

• Change to the device directory by entering the following instruction:

  /interface lte

• Configure the interface using commands in the form:

  set option=”value” 0

  where the options are: apn, user and password. The value for each option should have been issued to you by the network provider. If not, contact them for these settings.

  For example, the following sequence of commands are for a Vodafone data SIM:

/interface lte

set apn="internet" 0

set user="web" 0

set password="web" 0

• Enable the interface with the command:

  enable 0

• Add and enable the dhcp client on interface with the commands:

  /ip dhcp-client add interface=lte1

  /ip dhcp-client enable 0

• Test using the command:

  /ping www.guralp.com (or any other valid DNS or IP address)

  You should see the server respond and a report of the results appear in the command window.

4.1.4 Enable DHCP server and NAT

DHCP is enabled at the factory and this configuration should not need to be changed. The following procedure is only required if the DHCP configuration needs to be restored (e.g. on a system that has had a factory-reset).

• Run the DCHP setup by entering the command:

  /ip dhcp-server setup

• The following parameters should be entered at the appropriate prompts:

  DHCP server interface: ether1

  DHCP address space: 192.168.88.0/24

  Gateway for DHCP network: 192.168.88.1

  Addresses to give out: use IP addresses in the range 102.168.88.2 to 192.168.88.254.

  DNS server: set this to the IP address of the routerboard

  Lease time: 3d

• Enter the following command to complete the device configuration:

  /ip firewall nat add chain=srcnat action=masquerade out-interface=lte1

4.2 Testing the modem

• Ensure the routerboard has been set up as detailed in section 4.1 on page 6.

• You can view modem type and signal strength using following command:

  /interface lte info 0

  Within 40 seconds you should see a list of networks, each with a signal strength shown in dB. Typical values are shown in the following table.

Larger numbers mean a weaker signal. A very strong signal will display a strength of around -60dB. The system will still run at -100dB but there may be problems initiating and maintaining a connection if the signal is weaker than this.

• Type to quit the scan.

4.3 Using the modem

• Remove the power cable and the cable connecting the device to the PC.

• Close the lid of the Pelicase®

• Connect the 6-way NETWORK connector to the Ethernet output of the data source equipment (e.g. EAM).

• Connect a suitable antenna to the coaxial connector.

• Connect the 4-way POWER connector to a 10 V-28 V DC power supply.

• The system is now live and will be transmitting data to the mobile telecommunications provider's base station.

4.4 Using the modem with NAMs

A common use of the GPT is to connect using the gdi-link protocol to a Güralp NAM at a data-centre from either a remote EAM or a digital instrument with an integrated EAM, such as a 3TDE or 5TDE. It is usual for the NAM at the data-centre to be contactable via a fixed IP address and for the remote device to initiate the connection. No further configuration of the GPT is required to support this arrangement.

If, however, the NAM is to initiate the connection, it is important that the mobile service provide allocates a fixed IP address to the GPT. If this is not possible, a dynamic DNS service must be used, so that the NAM can contact the remote device via its DNS name.

In this scenario, the GPT must be configured to allow incoming connections to the attached device. The following command should be entered at the command line:

/ip firewall nat add chain=dstnat protocol=tcp dst-port=1565 action=dst-nat to-address=address to-ports=1565

Replace address with the IP address of the EAM or digital instrument.

1565 is the port number for the gdi_link_tx service. Other services can be enabled by re-entering this command with a different port number, such as 22 for ssh or 443 for https.