CHAPTER 7 Astlinux and Asterisk Installation on Embedded System Introduction 1. Asterisk can be installed on number of operating systems but keeping embedded system in mind the operating system chosen is Astlinux-1.0.3 with asterisk-1.8.11.1 and the embedded system is SOekris Net5501-70. Astlinux Installation 2. Astlinux can be installed by writing the compressed image file to a Compact Flash card of 32 megabytes or larger. The software used for writing the image on a CF card is PHYSDISKWRITE. With the help of this software an image in.iso or.img format can be burned on CF card. Astlinux Image Burning on CF card 3. In order to burn the image, all the partitions that already exist along with all the data in the header file of CF card must be erased. This can be done by erasing it manually in command prompt. For that CMD must be run as administrator and then on it a command diskpart is executed. This will display all the storage disks available. Desired disk can be selected by select disk <disk number> command. And when the required disk is selected it is cleaned by executing clean function.
Figure 7.1: Disk Cleaning 4. Now when the CF card is clean, the image in.img format can be burned. In Physdiskwrite software, first command prompt is opened as administrator. Then manually we reach to the location of file which is unzipped previously and then a command is given Physdiskwrite astlinux-1.0.3-asterisk-1.8.11.img.gz. Physdiskwrite will prompt you to choose the correct drive to write to. First run the program with no CF installed, and then again with the CF. Then It can be made sure that program is being written on correct CF card. Now when it is confirmed that CF card is being displayed by particular number. The next step should be implemented. Physdiskwrite will first display all the drives available and then asks for the number of drive to write the image on. Particular number of the CF card drive should be given and then approval for the next comment should be given with y. With this image of Astlinux will be burned on the CF card.
Figure 7.2: Image Burning On CF Card Accessing BIOS through Serial Port 5. Now when the image is burned the next step would be accessing BIOS of Soekris Net5501-70. There is a serial port available on the back of the casing, with Ethernet ports and power supply ports installed on either side. RS232 to USB converter with female D9 port is acquired and its female D9 port is installed in male port of net5501 box and USB console to USB port of the PC. In order to access the RS232 to USB converter on PC, its appropriate driver is installed and then any software should be acquired that can be used as a Terminal. Software used in this project is Tera Term. In Tera Term the setting first the serial port should be selected.
Figure 7.3: Serial Port Selection 6. The baud rate then is set to 19200 which is default of Soekris box. And rest of the configuration is kept as default.
Figure 7.4: Baud rate Selection Soekris Booting 7. Now Soekris box can be accessed by PC with the help of Tera Term. When the Soekris box is then hard booted a series of data starts appearing on tera term console. Initially below displayed information is displayed. Figure 7.5: BIOS Display
BIOS Update 8. Now CF card is plugged in Soekris box and hard booted again. At this instant Soekris box is unable to detect the CF card even after hard booting quite a times. This issue was occurring because of the fact that Soekris BIOS is of version 1.33 which is not the most current version. So Soekris box is updated first to the latest version which is 1.33c. In order to do that the latest version in binary form is downloaded from Soekris website and downloaded to Soekris box using XMODEM protocol. Download command was given to the BIOS and XMODEM protocol was used to transfer the binary image into the Soekris system. The Soekris BIOS now is updated to version 1.33c but the system still appears to not detect the CF card. When the system is then hard booted by manually plugging the power supply out and then plugging it in again, Soekris box will start detecting CF card and the boot process will begin.
Figure 7.6: BIOS Update Soekris Login 9. Now when the Soekris box has started detecting the CF card, the normal boot process will begin. Initially it will detect the CF card and Astlinux will be booted. It will take quite some time to load and all the process functioning that are happening will be displayed on the Tera Term software.
Figure 7.7: Booting Initialization 10. When the system will be booted, username and password will be asked. As default the username is root and password is astlinux. And when the password is given, PBX will be started.
Figure 7.8: PBX Login 11. Here one of the major problem that occur is that sometimes during booting, kernel stops in between booting and an it fails to find Astlinux medium and such kind of error occurs.
Figure 7.9: Astlinux Medium Error 12. This error occurs mainly that CF card is not used to work as a primary drive. We can set it to secondary drive by first pressing ctrl and P to enter monitor while booting starts, then give command set Flash to secondary. This action can be confirmed by giving show command. And while booting also plug a USB, so with this action USB will become the primary device and CF card will become secondary and the booting will be smooth. Key Disk Generation 13. Now when the system has started booting, the next step is how to make changes in the configuration files. One of the methods is using Tera Term and directly make changes in files using vi <file name> command. But it is difficult and not much tolerant
to errors. Second method can be that key disk is generated on USB. By this method we mean that all the configuration files which are of importance are copied on the USB and a partition is generated on the USB. Then that USB can be unplugged from Soekris box and accessed on any Linux environment and with the help of GUI those files can be altered and when that USB is plugged again into the Soekris box and hard booted. Kernel will look for the changes in the USB and update all the changes from USB. The Soekris Net4801 has a OHCI USB 1.1 port on the back far edge of the case, past the power connector. It seems to work pretty well for small amounts of writes in combination with a USB key disk for storing things like voice mail, Asterisk configurations, Astlinux configurations, DHCP leases, etc. To make it work u must be logged in as root and then a login prompt will appear. Insert USB disk into the port and some SCSI disk stuff scroll by on the console. Enter a few times to so that the prompt appears again. The next step will destroy any thing that i8s there on the USB so please backup any data that is there on the USB. Type genkd and follow along. Then type yes when inquired and key disk will be generated on the USB. If it does not work and and some error occurs like device mounted on dev/sda1, this means that this function is auto mounted on dev/sda1. So a path is needed to be given along with the genkd command. So for that confirm the USB path from the SCSI data that scrolled when you plugged you USB and give the path along with the command. E.g. if your USB is mounted on path /dev/sdc1/, then instead of command genkd give command genkd /dev/sdc1. With this your key disk will be generated on the usb and it can be taken out and altered in any other Linux environment with GUI. Web GUI 14. One of the other methods is to access the web GUI of Soekris box. To make it happen some alterations are made in rc.conf file. The single configuration file rc.conf, resides at /etc/rc.conf. Once the procedure above is complete, rc.conf file can be altered in vi too. This file is pretty self-explanatory, and full of comments to make it easier to understand. If any changes are made in this file, the best way to apply them is
just to restart. The GUI can be accessed by going to the IP address (on the LAN interface) of the machine and using https://[insert ip here]. The default is 192.168.101.1, so the full URL is https://192.168.101.1.some warning messages will be displayed about the Certificate not being trusted, not matching the site, having an IP address of 0.0.0.0, etc. when the security certificate is confirmed, username and password will be asked. The default is admin and astlinux. 15. All the major changes can now be done in this web GUI. In the first tab status of this GUI general features about PBX are displayed along with names of all sip phones registered, disk usage, and general message log for Soekris box. Figure 7.10: Status 16. In next tab CDR log i.e. call detail record log, all the calls that happened from the server are mentioned along with their extension numbers, time of call and context which is accessed for that call.
Figure 7.11: CDR Log 17. In network tab, all the Ethernet port configurations are mentioned and their IP addresses can be accessed and altered from here. Soekris box has 4 Ethernet ports. Eth0 is for WAN while eth1, eth2, eth3 are used for LAN.
Figure 7.12: Network 18. In edit tab, all the major configuration files of dial plan can be accessed and altered. There is also an option for asterisk modules saving and asterisk server restart option here. The positive aspect of using this method is that Soekris box is not required to be hard booted every time any changes are made. Figure 7.13: Edit 19. The system tab can be used in general to change management password, to view, configure, reload and reboot system and configuration files. Along with these options, system firmware, asterisk sound packages and runnix boot loader can be upgraded from here.
Figure 7.14: System Persistent Storage 20. The sound packages in Soekris box are not installed by default. They are to be done manually and to make this happen, first persistent storage is to be made in the system. For making persistent storage, first the IP address https://<ip address>/admin/setup.php is accessed and step 1 is taken by choosing the appropriate option for the system.
Figure 7.15: Persistent Storage 21. When the continue option is selected in step 1, the system will be rebooted and after when the system is rebooted completely the same web page is accessed again and setup is completed by choosing the finish option.
Figure 7.16: Persistent Storage Format 22. Astlinux management will prompt when the installation procedure is complete. After that sound packages can be updated by accessing the system tab and connecting to internet from WAN port of Soekris box i.e. eth0 port.
Figure 7.17: Setup Compilation