Dhcpd lease time

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You can customize the lease duration for the dhcp server (dhcpd) in SME using these instructions.

Create custom template fragments

The commands below will create custom template fragments for default-lease-time and max-lease-time, re-generate /etc/dhcpd.conf, and restart the dhcpd service in order to activate your changes.

mkdir -p /etc/e-smith/templates-custom/etc/dhcpd.conf
cd  /etc/e-smith/templates-custom/etc/dhcpd.conf
echo "    default-lease-time  {21*86400};"      > 25LeaseTimeDefault
echo "    max-lease-time      {21*86400};"      > 25LeaseTimeMax
expand-template /etc/dhcpd.conf
sv restart dhcpd

Notes

• Replace "21" with the desired number of days.
• The spaces in front of "default-lease-time" and "max-lease-time" are important!
• SME default 'default-lease-time' is 1 day (86400 seconds).
• SME default 'max-lease-time' is 7 days (7*86400 = 604800 seconds).
• The SME expand-template command performs the calculation inside the braces and puts the results into the output file without braces.

Verify your changes

Verify that your changes "stuck" by looking at the actual values in /etc/dhcpd.conf:

grep lease-time /etc/dhcpd.conf

The above sample, using {21*86400}, produces the following in /etc/dhcpd.conf:

   default-lease-time  1814400;
   max-lease-time      1814400;

Un-Do these customizations

You can un-do these customizations with:

rm -f /etc/e-smith/templates-custom/etc/dhcpd.conf/25LeaseTimeDefault
rm -f /etc/e-smith/templates-custom/etc/dhcpd.conf/25LeaseTimeMax
expand-template /etc/dhcpd.conf
sv restart dhcpd