Letsencrypt/証明書/revokeについて、ここに記述してください。

$ ./letsencrypt-auto revoke -a manual -d gs.qmail.jp --server https://acme-v01.api.letsencrypt.org/directory --agree-dev-preview

Updating letsencrypt and virtual environment dependencies.......
Running with virtualenv: sudo /home/tmaeno/.local/share/letsencrypt/bin/letsencrypt revoke -a manual -d gs.qmail.jp --server https://acme-v01.api.letsencrypt.org/directory --agree-dev-preview
usage: 
  letsencrypt [SUBCOMMAND] [options] [-d domain] [-d domain] ...

The Let's Encrypt agent can obtain and install HTTPS/TLS/SSL certificates.  By
default, it will attempt to use a webserver both for obtaining and installing
the cert. Major SUBCOMMANDS are:

  (default) run        Obtain & install a cert in your current webserver
  certonly             Obtain cert, but do not install it (aka "auth")
  install              Install a previously obtained cert in a server
  revoke               Revoke a previously obtained certificate
  rollback             Rollback server configuration changes made during install
  config_changes       Show changes made to server config during installation

letsencrypt: error: argument --cert-path is required