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If you are looking for information about standard commands and utilities, they are on a different page.
No password is necessary to access the physical console terminal. Physical access control is assumed.
When connecting to an 8800 remotely using SSH, the default root password is evi-8800. EVI did not create any other login accounts on the 8800, as it is not intended as a multi-user host.
All of the support programs for autonomous operation of the 8800 are stored in /evi/mx8800. The MUX-A and MUX-B NFS shares are mounted at /evi/mx8800/muxa and /evi/mx8800/muxb, respectively.
The first part of Linux's boot sequence is determined by the kernel itself and cannot be altered without rebuilding the kernel from scratch.
Once the kernel's core is booted, it runs the mx8800.init script file (located on the root of the CompactFlast (CF) and later on the root of the RAM drive). The mx8800.init script creates a RAM drive and copies the entire (used part only) CF to it. Then Linux is switched from the CF to the RAM drive and the boot sequence continues, using the script file named /etc/init.d/rcS. The rcS script remounts the root directory of the RAM drive (/) for read/write, sets the network configuration (using information stored in /etc/netconfig), mounts the CF at /flash, starts the various system services that the 8800 uses and, finally, starts the script named /evi/mx8800/init in the background and finishes.
The/evi/mx8800/init script first sets up the environment variables that the script and the 8800 software will use, attempts to mount the NFS shares from MUX-A and/or MUX-B, runs the CheckNet application to get the name of the 8800 program to be used, and then starts the soft watchdog (w88) and the 8800 (which was copied into a local file named 8800prog). Lastly, the script checks the 8800's exit code to determine if it should loop, exit to the shell, or reboot the machine.
Primary boot script, creates RAM drive and replicates CF into it, then makes the RAM drive primary and runs /etc/init.d/rcS.
Configures the network interface and services used by the 8800 system. Finally, it runs /evi/mx8800/init.
Main 8800 control script. Loops until the 8800 indicates that it should either exit or reboot the machine.
Contains the IP addresses and network masks for the 8800 and the MUX nodes.
Tells the time synch program (chronyd) where to look for time servers, and some things about how they are to be used.
These two scripts remount the CompactFlash (at /flash) in read only and read/write mode, respectively. If you need to modify a configuration setting permanently, you must remount the flash for read/write and update the file there or else your changes will be lost on the next boot.
Under the standard Linux 8800 configuration, the 8800 init script has a process ID (PID) of 105, the watchdog's PID is 145 and the 8800's is 146. The noboot script attempts to kill all of these processes, preventing any of them from rebooting the system (which they are designed to do in the event of a problem). This may be handy when you have an 8800 that seems to boot quickly for unknown reasons.
These scripts run the nc8800stat program (the 8800's MMI) from either MUX-A or MUX-B's NFS share, respectively.
These scripts replace the /etc/init.d/rcS script with one configured to send the syslog to a local, circular memory buffer (accessible with the logread command) or also to the syslog port on MUX-A or MUX-B, respectively. Running EVI's SysLog program on the appropriate MUX will allow you to capture the log from the 8800. After using these commands to change the syslog setting, you must reboot the 8800 to have the changes take effect.
This script is used to reconfigure the IP address that is currently set in an 8800's CompactFlash. The identity of the 8800's is determined by their IP address. This command should be used prior to using one 8800 as a replacement for another.
In the 8800 home directory you might also notice other files.
CheckNet writes this file out. It contains the name of the file on the MUX that is the 8800 executable to be run. The init script uses the file for log messages, and to copy the file from the MUX into the local file named 8800prog and then executes 8800prog.
This application creates a shared memory region that the 8800 and nc8800stat use to determine current time sync status. It uses chronyd's UDP interface to access the time sync data directly from the time sync task.
These files contain the ID numbers of the shared memory regions created by ccheck and the 8800, respectively. The SHMID is used by other applications (like nc8800stat) to access the shared regions.
The CheckNet application is responsible for locating the primary MUX and determining what 8800 application needs to be run on the 8800. This allows the CF to be generic, while the hardware-specific component of the 8800 is loaded from the MUX under the direction of PICS. The configuration file contains settings for various numbers of retries and probably needn't be changed.
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