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DA-681 Series Linux Manual

Fourth Edition, August 2012

www.moxa.com/product

Summary of content (65 pages)

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DA-681 Series Linux Manual The software described in this manual is furnished under a license agreement and may be used only in accordance with the terms of that agreement. Copyright Notice © 2012 Moxa Inc. All rights reserved. Trademarks The MOXA logo is a registered trademark of Moxa Inc. All other trademarks or registered marks in this manual belong to their respective manufacturers.
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Table of Contents 1. Introduction ...................................................................................................................................... 1-1 Overview ........................................................................................................................................... 1-2 Product Features ................................................................................................................................ 1-2 Software Specifications............
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1 1. Introduction Thank you for purchasing the Moxa DA-681 Series of x86 ready-to-run embedded computers. This manual introduces the software configuration and management of the DA-681-LX, which runs the Linux operating system. For hardware installation, connector interfaces, setup, and upgrading the BIOS, please refer to the “DA-681 Series Hardware User’s Manual.” Linux is an open, scalable operating system that allows you to build a wide range of innovative, small footprint devices.
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DA-681 Linux Introduction Overview The DA-681 embedded computer is based on the Intel Celeron M processor and 910GMLE chipset, which supports standard X86 VGA, USB, PS/2 keyboard/mouse, 6 10/100 Mbps LAN ports, and SATA disk interface. In addition, the DA-681 supports a CompactFlash Socket and pre-installed embedded ready-to-run operating system. Programmers will find the full-function development kit a great benefit for developing software and building reliable communication applications.
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DA-681 Linux Introduction AP User Applications API Daemon (Apache, Telnet, FTPD) Application Interface (POSIX, Socket, Secure Socket) Protocol Stack TCP, IP, UDP, CMP, ARP, HTTP, SNMP, SMTP File System Linux Kernel Device Driver PCMCIA, CF, WLAN, USB, UART, RTC, VGA Micro Kernel Memory Control, Schedule, Process Hardware RS-232/422/485, Ethernet, PCMCIA, CompactFlash, SATA, USB ATTENTION Refer to http://www.debian.org/ and http://www.gnu.
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DA-681 Linux Introduction Component Version Description bsdmainutils 6.1.6 Collection of more utilities from FreeBSD bsdutils 2.12r-19etch1 Basic utilities from 4.4BSD-Lite busybox 1.1.3-4 Tiny utilities for small and embedded system console-common 0.7.69 Basic infrastructure for text console configuration console-data 1.01-7 Keymaps, fonts, charset maps, fallback table for console-tools 0.2.3dbs-65 Linux console and font utilities coreutils 5.97-5.3 The GNU core utilities cpio 2.
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DA-681 Linux Component Introduction Version Description klibc-utils 1.4.34-2 Small statically-linked utilities built with klibc klogd 1.4.1-18 Kernel Logging Daemon libacl1 2.2.41-1 Access control list shared library libattr1 2.4.32-1 Extended attribute shared library libbind9-0 9.3.4-2etch1 BIND9 Shared Library used by BIND libblkid1 1.39+1.40-WIP-2006 11.14+dfsg-2etch1 block device id library . klibc 1.0.3-6 Small statically-linked utilities built with klibc libc6 2.3.6.
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DA-681 Linux Introduction Component Version Description libnet-telnet-perl 3.03-1 Script telnetable connections libnewt0.52 0.52.2-10 Not Erik’s Windowing Toolkit - text mode windowing with slang libnfsidmap2 0.18-0 An nfs idmapping library libopencdk8 0.5.9-2 Open Crypto Development Kit (OpenCDK) (runtime) libpam-modules 0.79-5 Pluggable Authentication Modules for PAM libpam-runtime 0.79-5 Runtime support for the PAM library libpam0g 0.
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DA-681 Linux Component Introduction Version Description linux-kernel-headers 2.6.18-7 Linux Kernel Headers for development locales 2.3.6.ds1-13etch5 GNU C Library: National Language (locale) data [support] lockfile-progs 0.1.10 Programs for locking and unlocking files and mailboxes login 4.0.18.1-7 System login tools logrotate 3.7.1-3 Log rotation utility lsb-base 3.1-23.2etch1 Linux Standard Base 3.1 init script function make 3.81-2 The GNU version of the “make” utility. makedev 2.
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DA-681 Linux Introduction Component Version Description tcpd 7.6.dbs-13 Wietse Venema's TCP wrapper utilities tcpdump 3.9.5-2etch1 A powerful tool for network monitoring and data acquisition telnet 0.17-34 The telnet client telnetd 0.17-34 The telnet server tftpd 0.17-15 Trivial file transfer protocol server time 1.7-21 The GNU time program for measuring cpu resource usage traceroute 1.
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2 2. Software Configuration In this chapter, we explain how to operate a DA-681-LX computer directly or from a PC near you. There are three ways to connect to the DA-681-LX computer: through VGA monitor, by using Telnet over the network, or by using an SSH console from a Windows or Linux machine. This chapter describes basic Linux operating system configurations. The advanced network management and configuration will be described in the next chapter “Managing Communications.
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DA-681 Linux Software Configuration Starting from a VGA Console Connect the display monitor to the DA-681-LX VGA connector, and then power it up by connecting it to the power adaptor. It takes about 30 to 60 seconds for the system to boot up. Once the system is ready, a login screen will appear on your monitor. To log in, type the login name and password as requested. The default values are both root. Login: root Password: root login as: root root@192.168.3.
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DA-681 Linux Software Configuration Use a cross-over Ethernet cable to connect your development workstation directly to the target computer, or use a straight-through Ethernet cable to connect the computer to a LAN hub or switch. Next, use a Telnet client on your development workstation to connect to the target computer. After a connection has been established, type the login name and password as requested to log on to the computer. The default values are both root.
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DA-681 Linux Software Configuration Windows Users Click on the link http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html to download PuTTY (free software) to set up an SSH console for the DA-681-LX in a Windows environment. The following screen shows an example of the configuration that is required. Linux Users From a Linux machine, use the ssh command to access the DA-681-I-LX’s console utility via SSH. #ssh 192.168.3.127 Select yes to open the connection. [root@bee_notebook root]# ssh 192.
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DA-681 Linux Software Configuration # date MMDDhhmmYYYY MM: Month DD: Date hhmm: Hour and Minute YYYY: Year Use the following command to write the current system time to the RTC. # hwclock –w Moxa:~# date Fri Jun 23 23:30:31 CST 2000 Moxa:~# hwclock Fri Jun 23 23:30:35 2000 -0.557748 seconds Moxa:~# date 120910002004 Thu Dec 9 10:00:00 CST 2004 Moxa:~# hwclock –w Moxa:~# date ; hwclock Thu Dec 9 10:01:07 CST 2004 Thu Dec 9 10:01:08 2004 Moxa:~# -0.
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DA-681 Linux Software Configuration Updating the Time Automatically This section describes how to use a shell script to update the time automatically. Example shell script for updating the system time periodically #!/bin/sh ntpdate time.nist.gov # You can use the time server’s ip address or domain # name directly. If you use domain name, you must # enable the domain client on the system by updating # /etc/resolv.conf file. hwclock –w sleep 100 # Updates every 100 seconds. The min. time is 100 seconds.
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DA-681 Linux Software Configuration Enabling and Disabling Daemons The following daemons are enabled when the DA-681-LX boots up for the first time. • snmpd SNMP Agent Daemon • telnetd Telnet Server/Client Daemon • inetd • ftpd FTP Server/Client Daemon • sshd Secure Shell Server Daemon • httpd Internet Daemons Apache WWW Server Daemon Type the command ps –ef to list all processes currently running.
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DA-681 Linux Software Configuration # !/bin/sh # Add the daemonyou want to run daemon /root/tcps2-release & 5. After you finish writing or modifying the code, remember to execute “umount /” to change the root directory back to Read-only mode. Moxa:~# umount / 6. You should be able to find the enabled daemon after you reboot the system.
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DA-681 Linux Software Configuration MOXA:~# cd /etc/rc2.d MOXA:/etc/rc2.d# MOXA:/etc/rc2.d# ls S19nfs-common S25nfs-user-server S20snmpd S55ssh S24pcmcia S99showreadyled S99rmnologin MOXA:/etc/rc2.d# MOXA:/etc/rc2.d# ln –s /root/tcps2-release S60tcps2 MOXA:/etc/rc2.d# ls S19nfs-common S25nfs-user-server S20snmpd S55ssh S24pcmcia S60tcps2 MOXA:/etc/rc2.d# S99rmnologin S99showreadyled The command SxxRUNFILE has the following meaning: S: xx: Start the run file while Linux boots up.
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DA-681 Linux Software Configuration 1. Write a shell script named fixtime.sh and save it to /home/. #!/bin/sh ntpdate time.nist.gov hwclock –w exit 0 2. Change mode of fixtime.sh # chmod 755 fixtime.sh 3. Modify /etc/crontab file to run fixtime.sh at 8:00 every day. Add the following line to the end of crontab: *8*** root /home/fixtime.sh Inserting a SATA Hard Drive into the Computer The DA-681 offers one hard drive connector supporting a SATA-based disk that can be added to the computer.
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DA-681 Linux Software Configuration title Debian GNU/Linux, kernel 2.6.18-5-686 (single-user mode) kernel /boot/vmlinuz-2.6.18-5-686 root*/dev/sdb1 ro single root (hd0,0) initrd /boot/initrd.img-2.6.18-5-686 savedefault 3. Edit the /etc/fstab file and change the selected hard disk for system bootup. # /etc/fstab: static file system information.
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DA-681 Linux Software Configuration ATTENTION Remember to type the command # sync before you disconnect the USB storage device. If you do not issue the command, you may lose data. ATTENTION Remember to exit the /media/usb0 or /media/usb1 directory when you disconnect the USB storage device. If you stay in /media/usb0 or /media/usb1, the automatic un-mount process will fail. If that happens, type # umount /media/usb0 to un-mount the USB device manually.
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DA-681 Linux Software Configuration APT—Installing and Removing Packages APT is the Debian tool used to install and remove packages. Before installing a package, you need to configure the apt source file, /etc/apt/sources.list, which is located in the read-only partition. 1. Mount the root file system with write permission. MOXA:~# mount -o remount,rw /dev/hda1 / 2. Next, configure the /etc/apt/sources.list using vi editor. MOXA:~# vi /etc/apt/sources.list deb http://archive.debian.
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DA-681 Linux MOXA:~# df -h Filesystem rootfs udev Software Configuration Size Used Avail Use% Mounted on 790M 219M 531M 30% / /dev/hdb1 /dev/hdb1 tmpfs none /dev/mtdblock0 MOXA:~# 10M 44K 10M 1% /dev 790M 219M 531M 30% / 790M 219M 531M 30% /dev/.static/dev 248M 248M 161M 0 248M 13M 236M 0% /dev/shm 6% /tmp 25M 136M 16% /home ATTENTION You can free up the cache space with the command # apt-get clean MOXA:~# apt-get clean MOXA:~# WDT (Watchdog Timer) 1.
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DA-681 Linux } Software Configuration ioctl(swtd_fd, IOCTL_SWATCHDOG_ACK, NULL); … } close(swtd_fd); For convenient programming, we re-package these IO control commands in a convenient API in libswtd.c like this. int swtd_open(void) Description Open the file handle to control the sWatchDog. If you want to do something you must first to this. And keep the file handle to do other. Input None Output The return value is file handle. If has some error, it will return < 0 value.
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DA-681 Linux Software Configuration unsigned long *time – the function will return the current time period. Output: OK will be zero. The other has some error, to get error code from errno(). int swtd_ack(int fd) Description: Acknowledge sWatchDog. When the user application enable sWatchDog. It need to call this function periodically with user predefined time in the application program. Input: int fd - the file handle from swtd_open() return value. Output: OK will be zero.
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DA-681 Linux } Software Configuration exit(0); /* * The convenient watchdog API --- libswtd.c */ #include #include #include
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DA-681 Linux Software Configuration struct timeval } time; time.tv_sec = msec / 1000; time.
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DA-681 Linux } Software Configuration return ioctl(fd, IOCTL_SWATCHDOG_DISABLE, NULL); int swtd_get(int fd, int *mode, unsigned long *time) { struct { int mode; unsigned long time; } nowset; int ret; } ret = ioctl(fd, IOCTL_SWATCHDOG_GET, &nowset); *mode = nowset.mode; *time = nowset.time; return ret; int swtd_ack(int fd) { return ioctl(fd, IOCTL_SWATCHDOG_ACK, NULL); } int swtd_close(int fd) { return close(fd); } The makefile is shown below: all: gcc xxxx.c libswtd.
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3 3. Managing Communications The DA-681-LX ready-to-run embedded computer is a network-centric platform designed to serve as a front-end for data acquisition and industrial control applications. This chapter describes how to configure the various communication functions supported by the Linux operating system.
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DA-681 Linux Managing Communications Changing the Network Settings The DA-681-LX computer has6 Ethernet ports named LAN1 to LAN6. The LAN Port Expansion Module supports an additional four 10/100 Mbps Ethernet ports named LAN5 to LAN8. The default IP addresses and netmasks of the network interfaces are as follows: Default IP Address Netmask LAN 1 192.168.3.127 255.255.255.0 LAN 2 192.168.4.127 255.255.255.0 LAN 3 192.168.5.127 255.255.255.0 LAN 4 192.168.6.127 255.255.255.0 LAN 5 192.168.5.
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DA-681 Linux Managing Communications Dynamic IP Address using DHCP To configure one or both LAN ports to request an IP address dynamically, replace static with dhcp and then delete the rest of the lines. # The primary network interface allow-hotplug eth0 iface eth0 inet dhcp After modifying the boot settings of the LAN interface, issue the following command to activate the LAN settings immediately. # /etc/init.d/networking restart MOXA:~# /etc/init.
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DA-681 Linux Managing Communications Disabling the Telnet Server Disable the daemon by typing “#” in front of the first character of the row to comment out the line. For example, to disable the Telnet server, use the following commands: discard dgram udp wait root /bin/discard discard stream tcp nowait root /bin/discard telnet stream tcp nowait root /bin/telnetd After you finish writing or modifying the code, remember to execute “umount /” to change the root directory back to Read-only mode.
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DA-681 Linux Managing Communications /etc/hostname 1. Mount the root file system with write permission. MOXA:~# mount -o remount,rw /dev/hda1 / 2. Edit /etc/hostname: MOXA:~# vi /etc/hostname MOXA 3. After you finish writing or modifying the code, remember to execute “umount /” to change the root directory back to Read-only mode. MOXA:~# umount / 4. Re-configure the hostname. MOXA:~# /etc/init.d/hostname.sh start 5. Check the new hostname. MOXA:~# hostname /etc/resolv.
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DA-681 Linux Managing Communications # `info libc "Name Service Switch"' for information about this file. passwd: compat shadow: compat group: compat hosts: files dns protocols: db files ethers: db files networks: services: rpc: netgroup: files db files db files nis Apache Web Server Default Homepage The Apache web server’s main configuration file is /etc/apache2/sites-available/default, with the default homepage located at /var/www/apache2-default/index.html.
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DA-681 Linux echo echo echo echo echo Managing Communications REMOTE_ADDR = $REMOTE_ADDR REMOTE_USER = $REMOTE_USER AUTH_TYPE = $AUTH_TYPE CONTENT_TYPE = $CONTENT_TYPE CONTENT_LENGTH = $CONTENT_LENGTH Before you modify the homepage, use a browser (such as Microsoft Internet Explore or Mozilla Firefox) from your PC to test if the Apache web server is working. Type the LAN1 IP address in the browser’s address box to open the homepage. For example, if the default IP address 192.168.3.
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DA-681 Linux Managing Communications Allow from all ... ... ... ... DocumentRoot /media/usb0/www Options FollowSymLinks AllowOverride None ... ... ScriptAlias /cgi-bin/ /media/usb0/www/cgi-bin/ AllowOverride None Options ExecCGI -MultiViews +SymLinksIfOwnerMatch Order allow,deny Allow from all ... 6.
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DA-681 Linux Managing Communications The DA-681-LX supports three types of IPTABLES: Filter tables, NAT tables, and Mangle tables. Filter Table—includes three chains: INPUT chain OUTPUT chain FORWARD chain NAT Table—includes three chains: PREROUTING chain—transfers the destination IP address (DNAT). POSTROUTING chain—works after the routing process and before the Ethernet device process to transfer the source IP address (SNAT). OUTPUT chain—produces local packets.
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DA-681 Linux Managing Communications IPTABLES Hierarchy The following figure shows the IPTABLES hierarchy.
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DA-681 Linux Managing Communications IPTABLES Modules The DA-681-LX supports the following sub-modules. Be sure to use the module that matches your application. arptable_filter.ko arp_tables.ko arpt_mangle.ko ip_conntrack_amanda. ko ip_conntrack_ftp.ko ip_conntrack_h323.ko ip_conntrack_netbios_ns. ip_conntrack_netlink.ko ip_conntrack_irc.ko ip_conntrack.ko ip_conntrack_pptp.ko ip_conntrack_proto_sctp. ko ko ip_conntrack_sip.ko ip_conntrack_tftp.ko ip_nat_amanda.ko ip_nat_ftp.
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DA-681 Linux Managing Communications -F: Flush the selected chain (all the chains in the table if none is listed). -X: Delete the specified user-defined chain. -Z: Set the packet and byte counters in all chains to zero. Examples: # iptables -L -n In this example, since we do not use the -t parameter, the system uses the default “filter” table. Three chains are included: INPUT, OUTPUT, and FORWARD. INPUT chains are accepted automatically, and all connections are accepted without being filtered.
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DA-681 Linux Managing Communications --sport: Source port number. -d: Destination address. --dport: Destination port number. -j: Jump target. Specifies the target of the rules; i.e., how to handle matched packets. For example, ACCEPT the packet, DROP the packet, or LOG the packet. Examples: Example 1: Accept all packets from the lo interface. # iptables –A INPUT –i lo –j ACCEPT Example 2: Accept TCP packets from 192.168.0.1. # iptables –A INPUT –i eth0 –p tcp –s 192.168.0.
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DA-681 Linux Managing Communications NAT Example The IP address of all packets leaving LAN1 are changed to 192.168.3.127 (you will need to load the module ipt_MASQUERADE): #ehco 1 > /proc/sys/net/ipv4/ip_forward #modprobe ipt_MASQUERADE #iptables –t nat –A POSTROUTING –o eth0 –j MASQUERADE Enabling NAT at Bootup In most real world situations, you will want to use a simple shell script to enable NAT when the DA-681-LX boots up. The following script is an example.
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DA-681 Linux Managing Communications /sbin/iptables -F /sbin/iptables -X /sbin/iptables -Z /sbin/iptables -F -t nat /sbin/iptables -X -t nat /sbin/iptables -Z -t nat /sbin/iptables -P INPUT ACCEPT /sbin/iptables -P OUTPUT ACCEPT /sbin/iptables -P FORWARD ACCEPT /sbin/iptables -t nat -P PREROUTING ACCEPT /sbin/iptables -t nat -P POSTROUTING ACCEPT /sbin/iptables -t nat -P OUTPUT ACCEPT # Step 3. Enable IP masquerade.
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DA-681 Linux Managing Communications ““ Send a return (null text followed by the usual return) ogin: username word: password Log in with username and password. Refer to the chat man page, chat.8, for more information about the chat utility. /dev/ Specify the callout serial port. 115200 The baud rate. debug Log status in syslog. crtscts Use hardware flow control between computer and modem (at 115200 this is a must).
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DA-681 Linux Managing Communications MOXA:~# ping 129.67.1.165 PING 129.67.1.165 (129.67.1.165): 56 data bytes 64 bytes from 129.67.1.165: icmp_seq=0 ttl=225 time=268 ms 64 bytes from 129.67.1.165: icmp_seq=1 ttl=225 time=247 ms 64 bytes from 129.67.1.165: icmp_seq=2 ttl=225 time=266 ms ^C --- 129.67.1.
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DA-681 Linux Managing Communications init "/usr/sbin/chat -v -f /etc/ppp/ppp-ttyM0.chat" # Set up routing to go through this PPP link defaultroute # Default modem (you better replace this with /dev/ttySx!) /dev/ttyM0 # Speed 115200 # Keep modem up even if connection fails persist crtscts modem 192.168.16.1:192.168.16.2 debug -detach Configure the chat script /etc/ppp/ppp-ttyM0.chat SAY '' 'Auto Answer ON\n' ATS0=1 Start the pppd dial-in service.
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DA-681 Linux Managing Communications 4. Edit the file /etc/ppp/pap-secrets and add the following: “username@hinet.net” * “password” * # ATTENTION: The definitions here can allow users to login without a # password if you don't use the login option of pppd! The mgetty Debian # package already provides this option; make sure you don't change that. # INBOUND connections # Every regular user can use PPP and has to use passwords from /etc/passwd * hostname "username@hinet.
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DA-681 Linux Managing Communications name username@hinet.net mtu 1492 mru 1492 defaultroute noipdefault ~ ~ "/etc/ppp/options.eth0" 5 lines, 67 characters Type your username (the one you set in the /etc/ppp/pap-secrets and /etc/ppp/chap-secrets files) after the name option. You may add other options as desired. 7. Set up DNS. If you are using DNS servers supplied by your ISP, edit the file /etc/resolv.
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DA-681 Linux Managing Communications for the DA-681-LX without worrying about the amount of disk space that will be available. The DA-681-LX supports only NFS client protocol. ATTENTION Click on the following links for more information about NFS. • http://www.tldp.org/HOWTO/NFS-HOWTO/index.html • http://nfs.sourceforge.net/nfs-howto/client.html The following procedures illustrate how to mount a remote NFS Server. 1. Scan the NFS Server’s shared directory.
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DA-681 Linux Managing Communications SNMPv2-MIB::snmpOutGetRequests.0 = Counter32: 0 SNMPv2-MIB::snmpOutGetNexts.0 = Counter32: 0 SNMPv2-MIB::snmpOutSetRequests.0 = Counter32: 0 SNMPv2-MIB::snmpOutGetResponses.0 = Counter32: 540 SNMPv2-MIB::snmpOutTraps.0 = Counter32: 0 SNMPv2-MIB::snmpEnableAuthenTraps.0 = INTEGER: disabled(2) SNMPv2-MIB::snmpSilentDrops.0 = Counter32: 0 SNMPv2-MIB::snmpProxyDrops.
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DA-681 Linux Managing Communications 2. Generate a preset shared key by typing the command: # openvpn --genkey --secret secrouter.key 3. Copy the file that is generated to the OpenVPN machine: # scp /etc/openvpn/secrouter.key 192.168.8.174:/etc/openvpn ATTENTION A preshared key is located at /etc/openvpn/secrouter.key. You can use it for testing purposes. We suggest creating a new key for non-testing purpose. 4.
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DA-681 Linux Managing Communications 6. On machine OpenVPN B, modify the remote address in configuration file /etc/openvpn/tap0-br.conf. # point to the peer remote 192.168.8.173 dev tap0 secret /etc/openvpn/secrouter.key cipher DES-EDE3-CBC auth MD5 tun-mtu 1500 tun-mtu-extra 64 ping 40 up /etc/openvpn/tap0-br.sh #comp-lzo 7. Next modify the routing table in /etc/openvpn/tap0-br.sh script file.
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DA-681 Linux Managing Communications ATTENTION You can create link symbols to start the OpenVPN service at boot time: # ln -sf /etc/init.d/openvpn /etc/rc2.d/S16openvpn To stop the service, you should create these links: # ln -sf /etc/init.d/openvpn /etc/rc0.d/K80openvpn # ln -sf /etc/init.d/openvpn /etc/rc6.d/K80openvpn 9. On each OpenVPN machine, check the routing table by typing the command # route Destination 192.168.5.0 192.168.4.0 192.168.3.0 192.168.30.0 192.168.8.0 Gateway Genmsk 0.0.0.0 255.
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DA-681 Linux Managing Communications Ethernet Bridging for Private Networks on the Same Subnet 1. Set up four machines, as shown in the following diagram. 2. The configuration procedure is almost the same as for the previous example. The only difference is that you will need to comment out the parameter up in /etc/openvpn/tap0-br.conf of OpenVPN A and /etc/openvpn/tap0-br.conf of OpenVPN B. # point to the peer remote 192.168.8.174 dev tap0 secret /etc/openvpn/secrouter.
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DA-681 Linux Managing Communications 2. On machine OpenVPN A, modify the remote address in configuration file /etc/openvpn/tun.conf. # point to the peer remote 192.168.8.174 dev tun secret /etc/openvpn/secrouter.key cipher DES-EDE3-CBC auth MD5 tun-mtu 1500 tun-mtu-extra 64 ping 40 ifconfig 192.168.2.173 192.168.4.174 up /etc/openvpn/tun.sh #----------------------------end----------------------------3. Next, modify the routing table in script file /etc/openvpn/tun.sh.
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DA-681 Linux Managing Communications The first argument of parameter ifconfig is the local internal interface and the second argument is the internal interface at the remote peer. $5 is the argument that the OpenVPN program passes to the script file. Its value is the second argument of ifconfig in the configuration file. 5. Check the routing table after you run the OpenVPN programs, by typing the command # route. Destination Gateway 192.168.4.0 192.168.4.174 255.255.255.0 UG 192.168.8.0 * 192.168.4.
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4 4. System Recovery The DA-681-LX is installed with the Embedded Linux operating system, which is located in the Flash DOM (CompactFlash card) shipped with the DA-681-LX computer. Although it happens rarely, you may find on occasion that operating system files and/or the disk file system are damaged. This chapter describes how to recover the Linux operating system.
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DA-681 Linux System Recovery Recovery Environment The recovery environment includes the DA-681-LX embedded computer and a bootable USB disk with the recovery programs and system image file. DA-681-LX Bootable USB DISK (recovery USB Port Recovery Procedure 1. Format an Empty USB Disk. a. Prepare a USB disk that has at least a 256 MB capacity. b. Format your USB disk with the HP USB Disk Format Tool. Open the utility and select the device and FAT file system. You need empty disk only.
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DA-681 Linux System Recovery b. Power on and press DEL to enter the bios setup menu. c. Select Advanced  Hard Disk Boot Priority and then press Enter. d. From the setup menu, use “↑” or “↓” to select the USB device e. Press “+” to move the selection up to the first priority, and press Esc to exit the setup menu. f. Make sure the first boot device is Hard Disk. If not, press Enter to change it. g. Select Exit  Save & Exit Setup and then press Enter. h. Choose Y to save to the CMOS and then exit.
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DA-681 Linux System Recovery 4. Recover the Linux system from a USB Disk. a. If the BIOS setup is correct, it will boot from the USB disk. Follow the steps below to set up recovery parameters. Welcome to PING (Partition Image Is Not Ghost)! This tool can be used to both backup a Ghost-like image of your hard disk and to restore your hard disk from such an image. Please, be aware that if you choose to restore your hard disk. All the data contained on this computer might be lost during the restoration.
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DA-681 Linux System Recovery d. Choose restore image from Local disk partition. PING (Partition Image Is Not Ghost)! Where do you want to save/restore your image to/from? Network share Local disk partition e. Choose ### Choose THIS if you want a restoration ### Choose the partition to backup Note that you cannot restore a partition to itself. So every partition but one (the destination) can be checked. Use SPACE to SELECT an entry.
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DA-681 Linux System Recovery g. Enter “\” to choose the root directory of the restoration image. Enter root directory containing your data (eg. \mydir\PartImage) \ h. Choose DA680_V1.0_Build_08031316 for the restoration image. Action and Available images for restoration … Choose Create_New_Image if you want a ghost-like images of your partitions. Choose Backup_Local_Hard_Driver if prefer a zip archive. DA680_V1.0_Build_08031316 Create_New_Image Backup_Local_Hard_Driver i.
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DA-681 Linux System Recovery 5. Set up the BIOS back to boot from DOM or CompactFlash Disk. a. Power on and press DEL to enter the bios setup menu. b. Select Advanced  Hard Disk Boot Priority and then press Enter. c. From the setup menu, use “↑” or “↓” to select the DOM or CompactFlash device. d. Press “+” to move the selection up to the first priority, and press Esc to exit the setup menu. e. Select Exit  Save & Exit Setup and then press Enter. f. Choose Y to save to the CMOS and then exit. g.