ELK Stack, meet VMWare Server. Since VMWare’s ESXi runs on some Linux kernel, it shares the logging facilities we’re familiar with on Linux systems. Going about forwarding syslog messages to a remote box is a bit different thou. Luckily, VMWare’s Knowledge Base is very thorough if you know where to look.
Monitor anything; this is what fills your head after playing with Elasticsearch, Logstash and Kibana.