PROBLEM: Another instance of Certbot is already running.

[Carmel NY]

FreeBSD 11.1 RELEASE-p5

I have been using the p5-certbot port without a problem until recently. It is being run via cron:  /usr/local/bin/certbot -q renew --pre-hook "service dovecot stop" --post-hook "service dovecot start". Until recently that worked fine. Now I have started receiving this error message:  "Another instance of Certbot is already running." Try as I might, I cannot find another instance of "certbot" running.

Apparently, the only way to correct the problem is to reboot the system. This only works until after the cron command has run one time, after which the problem resurfaces. I am hoping that someone might have a suggestion.

Thanks!

-- 
Carmel

"C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do it blows your whole leg off."