~/letsencrypt # ./certbot-auto renew --standalone --rsa-key-size 4096 --pre-hook "service nginx stop; service apache2 stop" --post-hook "service nginx start; service apache2 start" --dry-run
WARNING: unable to check for updates.

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Processing /etc/letsencrypt/renewal/*snip*
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2016-09-09 08:34:46,324:WARNING:certbot.renewal:Attempting to renew cert from /etc/letsencrypt/renewal/*snip*.conf produced an unexpected error: HTTPSConnectionPool(host='acme-staging.api.letsencrypt.org', port=443): Max retries exceeded with url: /directory (Caused by NewConnectionError('<requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x7ff8aca96c10>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution',)). Skipping.
** DRY RUN: simulating 'certbot renew' close to cert expiry
**          (The test certificates below have not been saved.)

All renewal attempts failed. The following certs could not be renewed:
  /etc/letsencrypt/live/*snip*/fullchain.pem (failure)
** DRY RUN: simulating 'certbot renew' close to cert expiry
**          (The test certificates above have not been saved.)
1 renew failure(s), 0 parse failure(s)