Log analytics

https://papertrailapp.com
https://www.loggly.com/
https://www.graylog.org/
http://www.moonlit-software.com
https://github.com/mcholste/elsa
https://www.elastic.co/products/logstash?elektra=home&storm=banner&iesrc=ctr
https://logentries.com
http://www.rsyslog.com/
https://docs.microsoft.com/en-us/azure/log-analytics/

for ngnix
http://nginx.org/en/docs/http/ngx_http_log_module.html