=== 虛擬化建置平台 ===

  * oVirt https://ovirt.org/
  * VMWare vSphere Hypervisor https://my.vmware.com/en/web/vmware/evalcenter?p=free-esxi6

=== 郵件相關 ===
  * DKIM 產生 https://dkimcore.org/tools/

=== SSL申請工具 ===
  * https://letsencrypt.osfipin.com