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Boottime

Regarding rc.local🔗

/etc/rc.local is a bash script that Linux executes at boot time. So it is a convenient place to put your own startup commands.

However, there are a few rules to remember. Failure to follow these rules is very likely to brick your box :

  • You need to double-check the script and, ideally, test a copy before updating the master copy in "/etc/". Syntax errors or other problems with the script are very likely to brick your box.
  • If the script executes potentially blocking operations, they should be executed as background processes. Execution of blocking operations in the foreground is very likely to brick your box.
  • The script should be guaranteed to make it to the end and to exit there as follows : exit 0
  • The script probably needs to be executable, though this isn’t confirmed for all distros. To make is executable, do chmod 755 /etc/rc.local

  • Processes that will use network, such as node.js apps, need to wait until the network comes up before doing setup operations.

    We are going to install a script named wait-ipv4.pl. If that script is properly configured, you can simply call it to pause the startup process of such processes until the network is ready to go

    If you are not able to configure wait-ipv4.pl properly, or if you would like to be on safe side, a sleep 60 command should provide sufficient delay

    Neither wait-ipv4.pl nor sleep 60 should be executed by /etc/rc.local in the foreground. These commands are for use in background processes only.

Setup some boot-time operations🔗

Create the directory /opt/boot/, copy setupdoc/files/boot-net-programs.sh into the directory and make the copy executable. For example.

#!/bin/bash -e
mkdir -p /opt/boot/
cd
cp -p setupdoc/files/boot-net-programs.sh /opt/boot/
chmod 755  /opt/boot/boot-net-programs.sh

Edit /opt/smkbin/wait-ipv4.pl. Confirm that the settings of $IFACE and $IPCONFIG are correct for the current box. To get the information needed to do so, Use ifconfig |grep up and then which ipconfig

Edit the script that you installed above. Modify it to use similar code to start network-related process that are not handled by other means.

Create an initial version of /etc/rc.local that looks like this

#!/bin/bash
/opt/boot/boot-net-programs.sh >& /dev/null &
exit 0

Important : Do not use #!/bin/bash -e above

Make file executable : chmod 755 /etc/rc.local