My latest progress with Letsencrypt webroot authentication integration into my CentminMod.com LEMP web stack https://community.centminmod.com/posts/20509/ - full automation of Letsencrypt SSL certificate deployment via my nginx vhost generator 
centmin.sh menu options via shell
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Centmin Mod 1.2.3-eva2000.09 - http://centminmod.com
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Centmin Mod Menu
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1). Centmin Install
2). Add Nginx vhost domain
3). NSD setup domain name DNS
4). Nginx Upgrade / Downgrade
5). PHP Upgrade / Downgrade
6). XCache Re-install
7). APC Cache Re-install
8). XCache Install
9). APC Cache Install
10). Memcached Server Re-install
11). MariaDB 5.2/5.5 & 10.x Upgrade Sub-Menu
12). Zend OpCache Install/Re-install
13). Install ioping.sh vbtechsupport.com/1239/
14). SELinux disable
15). Install/Reinstall ImagicK PHP Extension
16). Change SSHD Port Number
17). Multi-thread compression: pigz,pbzip2,lbzip2...
18). Suhosin PHP Extension install
19). Install FFMPEG and FFMPEG PHP Extension
20). NSD Re-install
21). Update - Nginx + PHP-FPM + Siege
22). Add Wordpress Nginx vhost + WP Super Cache
23). Update Centmin Mod Code Base
24). Exit
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Enter option [ 1 - 24 ] 2
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and nginx vhost command line wizard
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Enter vhost domain name to add (without www. prefix): le10.http2ssl.xyz
Create a self-signed SSL certificate Nginx vhost? [y/n]: y
To get Letsencrypt SSL certificate, you must already have updated intended
domain vhost name's DNS A record to this server's IP addresss.
If top level domain, DNS A record is needed also for www. version of domain
otherwise, Letsencrypt domain name validation will fail.
le10.http2ssl.xyz is not a top level domain
your server IP address: 104.152.214.220
current DNS A record IP address for le10.http2ssl.xyz is: 104.152.214.220
Abort this Nginx vhost domain setup to setup proper DNS A record(s) first? [y/n]: n
Obtain Letsencrypt Free SSL certificate (90 day expiry / renew every 60 days) ? [y/n]: y
