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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 :

  • Double-check the script and test a copy before updating the master copy in /etc/. Syntax errors or other issues with the script can render the system inoperable.
  • If the script executes potentially blocking operations, execute them as background processes. Running blocking operations in the foreground will likely cause the system to become unresponsive.
  • The script must complete execution and exit with the command exit 0.
  • The script must be executable, although this requirement is not confirmed for all distributions. To make it executable, run 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.

    Install the script named wait-ipv4.pl. If configured properly, call the script to pause the startup of processes until the network is ready.

    If configuring wait-ipv4.pl is not possible or to ensure safety, use the command sleep 60 to provide a 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