Problem with getting cfexecute tag to work

I am using Lucee 5.3.6.61 on Ubuntu and am trying to get this tag, which simply pings the localhost, to work (I have omitted the angle brackets otherwise the next line doesn’t appear):

cfexecute name="/bin/ping" arguments=“localhost” outputfile="/tmp/cfexecute_test_page.txt" timeout=“0” /cfexecute

but after about 60 seconds an error message appears saying ‘Error invoking external process’. The permissions of /bin/ping are:

-rwsr-xr-x 1 root root 64424 Jun 28 2019 /bin/ping

so it should be executable by anyone. I’m trying to get this very simple example to work on a dev server; there is another much bigger shell script on this server which works fine when executed using on a Coldfusion MX 7.1 production server but not at all under Lucee.

Any suggestions or pointers to what I’m doing wrong here will be gratefully received!

Andy