What is /dev/null 2>&1?
io-redirection, posix, shell, syntax
Solution
`>> /dev/null` redirects standard output (`stdout`) to `/dev/null`, which discards it.
(The `>>` seems sort of superfluous, since `>>` means append while `>` means truncate and write, and either appending to or writing to `/dev/null` has the same net effect. I usually just use `>` for that reason.)
`2>&1` redirects standard error (`2`) to standard output (`1`), which then discards it as well since standard output has already been redirected.
Problem
I found this piece of code in /etc/cron.daily/apf ``` #!/bin/bash /etc/apf/apf -f >> /dev/null 2>&1 /etc/apf/apf -s >> /dev/null 2>&1 ``` It's flushing and reloading the firewall. I don't understand the `>> /dev/null 2>&1` part. What is the purpose of having this in the cron? It's overriding my firewall rules. Can I safely remove this cron job?