# Schedule Proxmox VM Startup and Shutdown with Cron

## What is Cron?

> The cron daemon is a background process that runs particular programs at particular times (for example, every minute, day, week, or month), as specified in a crontab. By default, users may also create crontabs of their own so that processes are run on their behalf. -https://packages.debian.org/stable/cron

1. Log into Proxmox VE either via SSH or the web based shell
2. Run the following commands in the terminal
   # verify the location of qm
   # should output /usr/sbin/qm
   which qm
   # list the configured vms
   qm list
3. Note the VMID of the target VM(s)
4. Determine the startup and shutdown schedule requirements for each target VM
5. Convert the startup and shutdown schedules to cron format, https://crontab.guru/ is a great utility to visualize them
6. Continue with the following commands in the terminal
   # edit the cron table file
   crontab -e
   # if prompted, select nano from the list of editors
7. At the bottom of the file, add an entry for the start and stop of each target VM in the following format

   <%cron schedule%> /usr/sbin/qm <%start|shutdown%> <%VMID%>
   55 6 * * * /usr/sbin/qm start 100
   5 23 * * * /usr/sbin/qm shutdown 100

8. Press CTRL+O, Enter, CTRL+X to write the changes and close nano
9. In the example above, VM 100 will be started at 6:55 AM and shutdown at 11:05 PM everyday
10. Cron schedules can be extremely flexible with some creativity, some examples:

    6:55 AM only on weekdays
    55 6 * * 1-5 /usr/sbin/qm start 100
    9:00 AM only on weekends
    0 9 * * 6,0 /usr/sbin/qm start 100
    7:00 AM only on Monday, Wednesday and Friday
    0 7 * * 1,3,5 /usr/sbin/qm start 100

11. Linux Containers (lxc) can be controlled via the pct command

    55 6 * * 1-5 /usr/sbin/pct start 103
    0 9 * * 6,0 /usr/sbin/pct start 103
    0 7 * * 1,3,5 /usr/sbin/pct start 103