I've a multisite ISPconfig 3.1.8p1 on one server (VPS) with apache, mysql, postfix, etc. running about 21 sites (most of them WordPress). Some of them with SSL (LE). All humming nicely. Except for one site. This is also a WordPress site with LE SSL. This site somehow turns of pretty randomly (at least, the result is the same when I deactivate the [Active] option in the config. Visitors over http got one of the other pages without SSL (from another customer) and visitors over SSL got a certificate error because they also got rerouted to one of the SSL-sites of another customer. I've searched and searched what can cause this behaviour but I'm really in the woods and have no idea. Sometimes the site suddenly is up again for a few days... All the other site are working just fine! Anyone an idea how to figure out what is wrong?
Thanks Ahrasis, if the website is up the certificate is fine. Also when I do a # letsencrypt -n renew --apache It says: No renewals were attempted. All are valid. This afternoon when I checked on my phone, the website was on air again. As well https as http. A few hours later it was gone again. I also selected DEBUG for ISPConfig logging and studied the log for 24 hours. Only entry: 25.11.2017-13:57 - DEBUG - Calling function 'check_phpini_changes' from plugin 'webserver_plugin' raised by action 'server_plugins_loaded'. 25.11.2017-13:57 - DEBUG - Remove Lock: /usr/local/ispconfig/server/temp/.ispconfig_lock Pulling my hair here...
[update]: I discovered that this behaviour only occurs when I'm on my home network. When I'm on 4G, everything works normal. Somehow when I'm originated from my internet connection at home, ISPconfig (or Apache probably) shows not the site that it should but another site for https and again another site for http.
[update2]: Found the problem! This particular domain was registered with another domain provider. When checking DNS-settings with this provider it turned out that there was still a IPv6-entry of the server in the DNS-table. I've a full IPv6-connection at home, so I connected via IPv6. Interesting to note: when Apache doesn't know what to serve on IPv6, it randomly picks other sites from the queue, which explains the weird things I did see happening. [issue solved]
