Digi 6310-DX User manual

6310-DX
User Guide
User Guide
Firmware version 22.2

Revision history—90002313
Revision Date Description
F March 2021 Release of Digi 6310-DX firmware version 21.2:
nLocation services added, including:
lThe ability to define a static latitude and longitude
as a location for the device.
lGNSSsupport through the cellular modem
(requires the CM07 COREmodem).
lReporting location information as health metrics to
Digi Remote Manager.
lGeo-fencing: Allow you to define one or more
circular or polygonal geo-fence areas and then
perform a set of actions when the device enters or
leaves that area.
lPython support for location information through
the digidevice.location python module.
nCellular modem carrier scanning and locking:
lNew modem scan CLI command for listing
available carriers for the current modem and SIM.
lManual carrier selection option to allow you to lock
the SIM to a specific carrier.
nEnhanced serial support:
lCertificate management control for TCP and
autoconnect serial port setups.
lAutoconnect.
nLocal RESTAPI for automated configuration of the
device.
nSupport for remote CLI commands through Digi
Remote Manager.
nSupport for automatically checking for device and
modem firmware updates.
G June 2021 Release of Digi 6310-DX firmware version 21.5:
nWi-Fi enhancements:
lAdded support for WPA3 Wi-Fi encryption:
oWPA2/WPA3 Personal
oWPA3 Enhanced Open
oWPA3 Personal
lAdded support for WPA and WPA/WPA2 mised
6310-DX User Guide 2

Revision Date Description
mode with TKIP.
nCellular enhancements:
lAdded support for modem firmware update to the
Admin CLI.
lAdded support for over-the-air (OTA) modem
firmware update to check, list, and update to new
modem firmware from the Digi firmware server.
lAdded the ability to scan for cellular carriers on the
Modem status page and the ability select a
particular PLMN/network to use.
nAdded commands for over-the-air (OTA) system
firmware update to check, list, and update to new
firmware from the Digi firmware server.
nAdded a show dns command to the Admin CLI to
display active DNS servers and their associated
interface.
nAdded a show ntp command to the Admin CLI to
display the status of the NTP service.
nExpanded Port forwarding option to support a range of
ports, including one-to-one and many-to-one port
mappings.
nAdded options to control packet filtering for the
network analyzer.
nVPN enhancements:
lIPsec enhancements:
oAdded support for multiple remote endpoints
and the ability to use round-robin or to
randomly select an endpoint to establish a
tunnel to.
oAdded configurable options to control IKE
transmit interval, tunnel retry interval, and
tunnel retry timeout.
lLDAP enhancements:
oAdded a login attribute to provide the ability to
match the attribute set on an Active Directory
server.
nSureLink enhancements
lAdded the ability to configure how many times a
SureLink test must run, and must fail, before the
interface is restarted or the device is rebooted.
lAdded the ability to configure how many times a
SureLink test must pass before an interface is
6310-DX User Guide 3

Revision Date Description
considered to be working.
lAdded the ability to test another interface's status.
nSNMPv2 supported added.
nSimple Certificate Enrollment Protocol (SCEP)
supported added.
nUpdated python to version 3.6.13.
nAdded the default digi.device local domain.
H September 2021 Release of Digi 6310-DX firmware version 21.8:
nAdded LXC container support for running localized
containers on the device.
nAdded support for maintenance windows triggers to
control when a device is available for Digi Remote
Manager maintenance activity.
nVPNenhancements:
lAdded support for L2TPv3 tunneling.
lNew option to enable, disable, or force IPsec IKE
fragmentation.
nImproved options for creating a custom default
configuration:
lsystem backup CLI commands for generating a
custom default config file based on the active
config settings on the device.
lNew section on the File System page of the Web UI
for loading a configuration backup file as the
custom default config
lNew persistent files folder accessible through Digi
Remote Manager where users can upload a
configuration backup.
lAdded ability to clear a custom default
configuration by performing by pressing the ERASE
button, waiting for the device to reboot, then
pressing the ERASE again.
nAdded ability to override or edit SSH server options.
nAdded options for filtering Wi-Fi scanner results based
off of MAC addresses or RSSI signal strength.
nAdded options for sending local device event logs to
Digi Remote Manager.
nNew system time CLI command for manually setting
the local date and time.
nNew firewall packet filter options to allow/deny
packets based off of a range of source or destination
6310-DX User Guide 4

Revision Date Description
MAC addresses.
nNew monitoring metrics upload CLI command to
send on-demand health metrics to Digi Remote
Manager.
nAdded support for the configuration of custom scripts
that will be run manually, and a new system script
start CLI command to run manual scripts.
nNew "Find me" feature that flashes cellular-related
LEDs to help locate the device onsite and a new
system find-me command.
nEnabled passthrough mode on both cellular and wired
WAN connections by default.
nAdded datapoint.upload_multiple function to
digidevice python module for uploading multiple
datapoints to DigiRM at once.
nAdded clear dhcp-lease command to remove all
dynamic DHCP leases or certain DHCP leases based on
MAC address or IP address.
nAdded speedtest command for performing on-demand
iPerf or nuttcp speedtests.
nLocal users are now required to be assigned to an
authentication group.
nNew Network → Advanced → Sequential DHCP address
allocation configuration setting for controlling if DHCP
addresses are assigned sequentially or randomly
(disabled by default).
nAdded ability to control if DHCP addresses are assigned
sequentially or randomly (disabled by default).
nAdded 802.1x port-based network access control,
configurable per network interface.
J December 2021 Release of Digi 6310-DX firmware version 21.11:
nConfiguration option to allow for automatic update of
new firmware (disabled by default).
nUser authentication enhancements:
lAdded TACACS+ command authorization and
accounting for Admin CLI commands.
lAdded a new username alias to provide an
alternate username that allows for special
characters in the username.
nVPNenhancements:
lAdded support for PPP-over-L2TP tunnels.
6310-DX User Guide 5

Revision Date Description
lChanged default IPsec IKE DH group to 14 for
enhanced compatibility with industry standard
settings.
nLocation services enhancements:
lNew option for Location service to specify the
talker ID used in NMEA mesage strings.
lInclude the mode indicator field in NMEA messages
constructed when a GPS fix isn’t obtained.
nSureLink enhancments:
lAdded new settings under cellular Surelink options
to have the device reset the cellular modem if a
specified number of Surelink tests fail
lAdded show surelink Admin CLI command.
nSerial port enhancements:
lNew option to add and configure an external USB-
to-serial adapter.
lDisable serial history in remote access mode by
default.
nSupport for sending analog and digial I/O health
metrics to Digi Remote Manager.
nAdded show containers Admin CLI command.
K March 2022 Release of Digi 6310-DX firmware version 22.2:
nVPNenhancements:
lRenamed VPN >IPsec >Tunnels >Policies >Local
network setting to Local traffic selector and
added Remote traffic selector.
lAdded a Dynamic option to the Local traffic
selector to configuration of a local network by
protocol and/or port instead of a network address
range.
lAdded Protocol and Port match criteria for Local
traffic selector and Remote traffic selector.
lAdded VPN >IPsec >Advanced >Debug level to
specify the logging verbosity of IPsec messages in
the device system logs.
nEnhancements to communications with Digi Remote
Manager:
lEnhanced security for communications with Digi
Remote Manager by using client-side certificates.
lThe default URL for the device's Remote Manager
connection is now edp12.devicecloud.com. This
6310-DX User Guide 6

Revision Date Description
URL is required to utilize the client-side certificate
support.
nNew Switch SIM SureLink action for WWAN interfaces,
which allows SureLink to be configured to switch to the
alternate SIM if the modem is connected but SureLink
test are failing.
lNew Switch SIM fail count option to determine
how many SureLink failures are required prior to
switching to the alternate SIM.
nNew Socket ID string option to send the configured
text to the remote server(s) when a TCP socket
connection is opened to the serial port.
nNew cat Admin CLI command for displaying file
contents.
Trademarks and copyright
Digi, Digi International, and the Digi logo are trademarks or registered trademarks in the United States
and other countries worldwide. All other trademarks mentioned in this document are the property of
their respective owners.
© 2022 Digi International Inc. All rights reserved.
Disclaimers
Information in this document is subject to change without notice and does not represent a
commitment on the part of Digi International. Digi provides this document “as is,” without warranty of
any kind, expressed or implied, including, but not limited to, the implied warranties of fitness or
merchantability for a particular purpose. Digi may make improvements and/or changes in this manual
or in the product(s) and/or the program(s) described in this manual at any time.
Warranty
To view product warranty information, go to the following website:
www.digi.com/howtobuy/terms
Customer support
Gather support information: Before contacting Digi technical support for help, gather the following
information:
Product name and model
Product serial number (s)
Firmware version
Operating system/browser (if applicable)
Logs (from time of reported issue)
Trace (if possible)
6310-DX User Guide 7

Description of issue
Steps to reproduce
Contact Digi technical support: Digi offers multiple technical support plans and service packages.
Contact us at +1 952.912.3444 or visit us at www.digi.com/support.
Feedback
To provide feedback on this document, email your comments to
[email protected]
Include the document title and part number (6310-DX User Guide, 90002313 H) in the subject line of
your email.
6310-DX User Guide 8

Contents
Revision history—90002313 2
What's new in Digi 6310-DX version 22.2
Digi 6310-DX Quick start
Step 1: What's in the box 21
Step 2: Connect 23
Step 3: Power up 24
Step 4: Configure 24
Digi 6310-DX hardware reference
Hardware features 26
Device status LEDs 27
Signal quality indicators 28
Signal quality bars explained 28
LTE status indicators 29
QR code definition 30
Hardware setup
Site survey 32
Site survey troubleshooting 32
Physical installation 32
Connecting to the site network with local power 32
Install SIM cards in the Plug-in LTE modem 33
Apply Dielectric Grease over SIMContacts 33
Tips for improving cellular signal strength 34
Mount the 6310-DX device 34
Network integration 35
Enable router mode 35
Configuration and management
Review 6310-DX default settings 39
Local WebUI 39
Digi Remote Manager 39
Default interface configuration 39
6310-DX User Guide 9

6310-DX User Guide 10
Change the default password for the admin user 40
Enable router mode 42
Configuration methods 44
Using Digi Remote Manager 45
Access Digi Remote Manager 45
Configure the device to use aView for central management 45
Using the web interface 49
Log out of the web interface 51
Use the local RESTAPI to configure the 6310-DX device 51
Use the GETmethod to return device configuration information 51
Use the POST method to modify device configuration parameters and list arrays 53
Use the DELETE method to remove items from a list array 54
Using the command line 56
Access the command line interface 56
Log in to the command line interface 56
Exit the command line interface 57
Interfaces
Wide Area Networks (WANs) 59
Wide Area Networks (WANs) and Wireless Wide Area Networks (WWANs) 60
Configure WAN/WWAN priority and default route metrics 60
WAN/WWAN failover 63
Configure SureLink active recovery to detect WAN/WWAN failures 64
Configure the device to reboot when a failure is detected 75
Disable SureLink 83
Example: Use a ping test for WAN failover from Ethernet to cellular 87
Using Ethernet devices in a WAN 91
Using cellular modems in a Wireless WAN (WWAN) 91
Configure a Wide Area Network (WAN) 115
Configure a Wireless Wide Area Network (WWAN) 124
Show WAN and WWAN status and statistics 134
Delete a WAN or WWAN 136
Default outbound WAN/WWAN ports 137
Local Area Networks (LANs) 138
About Local Area Networks (LANs) 139
Configure a LAN 139
Show LAN status and statistics 147
Delete a LAN 149
DHCP servers 151
Create a Virtual LAN (VLAN) route 167
Default services listening on LANports 170
Bridging 171
Configure a bridge 172
Show Surelink status and statistics 175
Show Surelink status for all interfaces 175
Show Surelink status for a specific interface 176
Show Surelink status for all IPsec tunnels 176
Show Surelink status for a specific IPsec tunnel 177
Show Surelink status for all OpenVPN clients 177
Show Surelink status for a specific OpenVPN client 178

6310-DX User Guide 11
Routing
IP routing 180
Configure a static route 181
Delete a static route 184
Policy-based routing 186
Configure a routing policy 187
Example: Dual WAN policy-based routing 195
Example: Route traffic to a specific WAN interface based on the client MACaddress 198
Routing services 203
Configure routing services 204
Show the routing table 207
Dynamic DNS 208
Configure dynamic DNS 208
Virtual Router Redundancy Protocol (VRRP) 214
VRRP+ 214
Configure VRRP 215
Configure VRRP+ 218
Example: VRRP/VRRP+ configuration 226
Configure device one (master device) 227
Configure device two (backup device) 231
Show VRRP status and statistics 237
Virtual Private Networks (VPN)
IPsec 240
IPsec data protection 240
IPsec mode 240
IPsec modes 240
Internet Key Exchange (IKE) settings 240
Authentication 241
Configure an IPsec tunnel 241
Configure IPsec failover 268
Configure SureLink active recovery for IPsec 271
Show IPsec status and statistics 278
Debug an IPsec configuration 279
Configure a Simple Certificate Enrollment Protocol client 281
Example: SCEP client configuration with Fortinet SCEP server 286
Disable hardware cryptographic acceleration 290
OpenVPN 293
Configure an OpenVPN server 294
Configure an OpenVPN Authentication Group and User 303
Configure an OpenVPN client by using an .ovpn file 308
Configure an OpenVPN client without using an .ovpn file 311
Configure SureLink active recovery for OpenVPN 315
Show OpenVPN server status and statistics 323
Show OpenVPN client status and statistics 324
Generic Routing Encapsulation (GRE) 326
Configuring a GREtunnel 326
Show GRE tunnels 331
Example: GRE tunnel over an IPSec tunnel 332
L2TP 347
Configure a PPP-over-L2TP tunnel 347
Configure SureLink active recovery for PPP-over-L2TP 357

6310-DX User Guide 12
L2TP with IPsec 365
Show L2TP tunnel status 365
L2TPv3 Ethernet 367
Configure an L2TPv3 tunnel 367
Show L2TPV3 tunnel status 372
NEMO 373
Configure a NEMO tunnel 373
Show NEMO status 379
Services
Allow remote access for web administration and SSH 382
Configure the web administration service 385
Configure SSHaccess 395
Use SSH with key authentication 402
Generating SSH key pairs 402
Configure telnet access 405
Configure DNS 410
Show DNS server 416
Simple Network Management Protocol (SNMP) 417
SNMP Security 417
Configure Simple Network Management Protocol (SNMP) 417
Download MIBs 422
Location information 423
Configure the location service 424
Enable or disable modem GNSSsupport 426
Configure the device to use a user-defined static location 428
Configure the device to accept location messages from external sources 430
Forward location information to a remote host 435
Configure geofencing 442
Show location information 454
Modbus gateway 455
Configure the Modbus gateway 456
Show Modbus gateway status and statistics 469
System time 472
Configure the system time 472
Manually set the system date and time 476
Network Time Protocol 476
Configure the device as an NTP server 477
Show status and statistics of the NTP server 482
Configure a multicast route 483
Ethernet network bonding 486
Enable service discovery (mDNS) 488
Use the iPerf service 492
Example performance test using iPerf3 496
Configure the ping responder service 497
Example performance test using iPerf3 501
Applications
Configure scripts to run automatically 503
Task one: Upload the application 503
Task two: Configure the application to run automatically 505
Configure scripts to run manually 509

6310-DX User Guide 13
Task one: Upload the application 510
Task two: Configure the application to run automatically 511
Start a manual script 514
Stop a script that is currently running 515
Show script information 516
Run a Python application at the shell prompt 517
Start an interactive Python session 519
Digidevice module 521
Use digidevice.cli to execute CLI commands 522
Use digidevice.datapoint to upload custom datapoints to Digi Remote Manager 523
Use digidevice.config for device configuration 526
Use Python to respond to Digi Remote Manager SCI requests 528
Use digidevice runtime to access the runtime database 537
Use Python to upload the device name to Digi Remote Manager 539
Use Python to access the device location data 541
Use Python to set the maintenance window 545
Use Python to send and receive SMS messages 547
Use the Paho MQTTpython library 549
User authentication
6310-DX user authentication 555
User authentication methods 555
Add a new authentication method 557
Delete an authentication method 559
Rearrange the position of authentication methods 561
Authentication groups 563
Change the access rights for a predefined group 564
Add an authentication group 566
Delete an authentication group 570
Local users 572
Change a local user's password 573
Configure a local user 575
Delete a local user 583
Terminal Access Controller Access-Control System Plus (TACACS+) 586
TACACS+ user configuration 587
TACACS+ server failover and fallback to local authentication 588
Configure your 6310-DX device to use a TACACS+ server 588
Remote Authentication Dial-In User Service (RADIUS) 593
RADIUS user configuration 594
RADIUS server failover and fallback to local configuration 594
Configure your 6310-DX device to use a RADIUS server 595
LDAP 598
LDAP user configuration 600
LDAP server failover and fallback to local configuration 601
Configure your 6310-DX device to use an LDAP server 601
Configure serial authentication 606
Disable shell access 608
Set the idle timeout for 6310-DX users 610
Example user configuration 613
Example 1: Administrator user with local authentication 613
Example 2: RADIUS, TACACS+, and local authentication for one user 615

6310-DX User Guide 14
Firewall
Firewall configuration 623
Create a custom firewall zone 623
Configure the firewall zone for a network interface 625
Delete a custom firewall zone 627
Port forwarding rules 628
Configure port forwarding 628
Delete a port forwarding rule 633
Packet filtering 636
Configure packet filtering 636
Enable or disable a packet filtering rule 640
Delete a packet filtering rule 642
Configure custom firewall rules 644
Configure Quality of Service options 645
System administration
Review device status 658
Configure system information 659
Update system firmware 661
Manage firmware updates using Digi Remote Manager 661
Certificate management for firmware images 662
Downgrading 662
Dual boot behavior 666
Update cellular module firmware 667
Update modem firmware over the air (OTA) 668
Update modem firmware by using a local firmware file 669
Reboot your 6310-DX device 670
Reboot your device immediately 670
Schedule reboots of your device 671
Erase device configuration and reset to factory defaults 673
Configure the 6310-DX device to use custom factory default settings 677
Locate the device by using the Find Me feature 679
Configuration files 681
Save configuration changes 681
Save configuration to a file 682
Restore the device configuration 683
Schedule system maintenance tasks 686
Disable device encryption 691
Re-enable cryptography after it has been disabled. 692
Configure the speed of your Ethernet ports 693
Monitoring
intelliFlow 697
Enable intelliFlow 697
Use intelliFlow to display average CPU and RAMusage 700
Use intelliFlow to display top data usage information 701
Use intelliFlow to display data usage by host over time 703
Configure NetFlow Probe 704

6310-DX User Guide 15
Central management
Digi Remote Manager support 710
Certificate-based enhanced security 710
Configure Digi Remote Manager 710
Collect device health data and set the sample interval 717
Enable event log upload to Digi Remote Manager 720
Log into Digi Remote Manager 722
Use Digi Remote Manager to view and manage your device 723
Add a device to Digi Remote Manager 724
View Digi Remote Manager connection status 724
Configure multiple devices using profiles 726
Learn more 726
File system
The 6310-DX local file system 728
Display directory contents 728
Create a directory 729
Display file contents 730
Copy a file or directory 730
Move or rename a file or directory 731
Delete a file or directory 732
Upload and download files 733
Upload and download files by using the WebUI 733
Upload and download files by using the Secure Copy command 734
Upload and download files using SFTP 735
Diagnostics
Perform a speedtest 738
Generate a support report 738
View system and event logs 740
View System Logs 740
View Event Logs 742
Configure syslog servers 744
Configure options for the event and system logs 746
Analyze network traffic 751
Configure packet capture for the network analyzer 752
Example filters for capturing data traffic 761
Capture packets from the command line 762
Stop capturing packets 763
Show captured traffic data 764
Save captured data traffic to a file 765
Download captured data to your PC 766
Clear captured data 767
Use the ping command to troubleshoot network connections 769
Ping to check internet connection 769
Stop ping commands 769
Use the traceroute command to diagnose IProuting problems 769

6310-DX User Guide 16
Regulatory guide
Safety warnings
English 773
Bulgarian--б ъ л га р с ки 774
Croatian--Hrvatski 775
French--Français 776
Greek--Ε λληνικά 777
Hungarian--Magyar 778
Italian--Italiano 779
Latvian--Latvietis 780
Lithuanian--Lietuvis 781
Polish--Polskie 782
Portuguese--Português 783
Slovak--Slovák 784
Slovenian--Esloveno 785
Spanish--Español 786
End user license agreement
Command line interface
Access the command line interface 788
Log in to the command line interface 788
Exit the command line interface 789
Execute a command from the web interface 789
Display help for commands and parameters 790
The help command 790
The question mark (?) command 790
Display help for individual commands 791
Use the Tab key or the space bar to display abbreviated help 792
Auto-complete commands and parameters 792
Available commands 793
Use the scp command 794
Display status and statistics using the show command 795
show config 795
show system 796
show network 796
Device configuration using the command line interface 796
Execute configuration commands at the root Admin CLI prompt 797
Display help for the config command from the root Admin CLI prompt 797
Configuration mode 799
Enable configuration mode 799
Enter configuration commands in configuration mode 799
Save changes and exit configuration mode 800
Exit configuration mode without saving changes 800
Configuration actions 800
Display command line help in configuration mode 801
Move within the configuration schema 803
Manage elements in lists 804
The revert command 806
Enter strings in configuration commands 808

6310-DX User Guide 17
Example: Create a new user by using the command line 808
Command line reference 811
analyzer clear 812
analyzer save 813
analyzer start 813
analyzer stop 813
clear dhcp-lease ip-address 813
clear dhcp-lease mac 813
container create 814
container delete 814
cp 814
help 814
ls 816
mkdir 817
modem at 817
modem at-interactive 817
modem firmware check 817
modem firmware list 817
modem firmware ota check 818
modem firmware ota list 818
modem firmware ota update 818
modem firmware update 818
modem pin change 819
modem pin disable 819
modem pin enable 819
modem pin status 820
modem pin unlock 820
modem puk status 820
modem puk unlock 820
modem reset 821
modem scan 821
modem sim-slot 821
monitoring 821
monitoring metrics upload 822
more 822
mv 822
ping 822
reboot 824
rm 825
scp 826
show analyzer 826
show arp 826
show cloud 826
show config 827
show containers 827
show dhcp-lease 827
show dns 827
show event 827
show hotspot 828
show ipsec 828
show l2tp lac 828
show l2tp lns 828
show l2tpeth 829
show location 829
show log 829

6310-DX User Guide 18
show manufacture 829
show modbus-gateway 829
show modem 830
show nemo 830
show network 830
show ntp 830
show openvpn client 831
show openvpn server 831
show route 831
show serial 831
show scripts 832
show surelink interface 832
show surelink ipsec 832
show surelink openvpn 832
show system 833
show usb 833
show version 833
show vrrp 833
show web-filter 833
speedtest 834
ssh 834
system backup 834
system disable-cryptography 835
system duplicate-firmware 835
system factory-erase 835
system find-me 835
system firmware ota check 836
system firmware ota list 836
system firmware ota update 836
system firmware update 836
system power ignition off_delay 836
system restore 837
system script start 837
system script stop 837
system serial clear 837
system serial save 838
system serial show 838
system serial start 838
system serial stop 838
system support-report 838
system time set 839
system time sync 839
system time test 839
telnet 839
traceroute 840
Antenna notes and solutions
Antenna terminology 842
Physical specifications 842
Antennas tested by Digi 842
Extra-small IoT paddle antennas 843
Large external MIMO antenna (outdoor rated) 843
Flat MIMO antenna #1 844
Flat MIMO antenna #2 844

6310-DX User Guide 19
Paddle extender 845

What's new in Digi 6310-DX version 22.2
Release of Digi 6310-DX firmware version 22.2:
nVPNenhancements:
lRenamed VPN >IPsec >Tunnels >Policies >Local network setting to Local traffic
selector and added Remote traffic selector.
lAdded a Dynamic option to the Local traffic selector to configuration of a local network
by protocol and/or port instead of a network address range.
lAdded Protocol and Port match criteria for Local traffic selector and Remote traffic
selector.
lAdded VPN >IPsec >Advanced >Debug level to specify the logging verbosity of IPsec
messages in the device system logs.
nEnhancements to communications with Digi Remote Manager:
lEnhanced security for communications with Digi Remote Manager by using client-side
certificates.
lThe default URL for the device's Remote Manager connection is now
edp12.devicecloud.com. This URL is required to utilize the client-side certificate support.
nNew Switch SIM SureLink action for WWAN interfaces, which allows SureLink to be configured
to switch to the alternate SIM if the modem is connected but SureLink test are failing.
lNew Switch SIM fail count option to determine how many SureLink failures are required
prior to switching to the alternate SIM.
nNew Socket ID string option to send the configured text to the remote server(s) when a TCP
socket connection is opened to the serial port.
nNew cat Admin CLI command for displaying file contents.
6310-DX User Guide 20