How to grep exim command output in terminal?

Question

I expected this command to print some lines containing "routed by" string:

root@localhost:~# exim -bt -d [email protected] | grep "routed by"

But it listed full exim -bt -d [email protected] command output. Which command would do what I excepted? The OS is Debian Jessie.

Answer 1

The output goes to stderr, so redirect it:

$ exim -bt -d [email protected] 2>&1|grep routed\ by
routed by amavis router