443/tcp & 8000/tcp between ESXi hosts are the ports used for vMotion traffic, but you will probably want/need some vCenter Server-to-ESXi Host ports open as well.
This KB article has everything you ever wanted to know about TCP/UDP Port usage with VMware products.
http://kb.vmware.com/kb/1012382
However, I'll put the ESXi 5.x one's here to save you a bit of time and hassle, as the list is huge. You'll probably want to check the ports for vCenter Server 5.x too while you're at it.
| ESXi 5.x | 22 | TCP | Client PC | ESXi 5.x | SSH Server |
| ESXi 5.x | 53 | UDP | ESXi 5.x | DNS Server | DNS Client |
| ESXi 5.x | 68 | UDP | ESXi 5.x | DHCP Server | DHCP Client |
| ESXi 5.x | 80 | TCP | Client PC | ESXi 5.x | Redirect Web Browser to HTTPS Service (443) |
| ESXi 5.x | 88 | TCP | ESXi host | Active Directory Server | PAM Active Directory Authentication - Kerberos |
| ESXi 5.x | 111 | TCP | ESXi/ESX Host | NFS Server | NFS Client – RPC Portmapper |
| ESXi 5.x | 111 | UDP | ESXi/ESX Host | NFS Server | NFS Client – RPC Portmapper |
| ESXi 5.x | 123 | UDP | ESXi/ESX Host | NTP Time Server | NTP Client |
| ESXi 5.x | 161 | UDP | SNMP Server | ESXi 4.x Host | SNMP Polling. Not used in ESXi 3.x |
| ESXi 5.x | 162 | UDP | ESXi Host | SNMP Collector | SNMP Trap Send |
| ESXi 5.x | 389 | TCP/UDP | ESXi host | LDAP Server | PAM Active Directory Authentication - Kerberos |
| ESXi 5.x | 427 | UDP | VI / vSphere Client | ESXi/ESX Host | CIM Service Location Protocol (SLP) |
| ESXi 5.x | 443 | TCP | VI / vSphere Client | ESXi/ESX Host | VI / vSphere Client to ESXi/ESX Host management connection |
| ESXi 5.x | 443 | TCP | ESXi/ESX Host | ESXi/ESX Host | Host to host VM migration and provisioning |
| ESXi 5.x | 445 | UDP | ESXi host | MS Directory Services Server | PAM Active Directory Authentication |
| ESXi 5.x | 445 | TCP | ESXi host | MS Directory Services Server | PAM Active Directory Authentication |
| ESXi 5.x | 445 | TCP | ESXi host | SMB Server | SMB Server |
| ESXi 5.x | 464 | TCP | ESXi hostSee . | Active Directory Server | PAM Active Directory Authentication - Kerberos |
| ESXi 5.x | 514 | UDP/TCP | ESXi 5.x | Syslog Server | Remote syslog logging |
| ESXi 5.x | 902 | TCP/UDP | ESXi 5.x | ESXi 5.x | Host access to other hosts for migration and provisioning |
| ESXi 5.x | 902 | TCP | vSphere Client | ESXi 5.x | vSphere Client access to virtual machine consoles (MKS) |
| ESXi 5.x | 902 | TCP/UDP | ESXi 5.x | vCenter Server | (UDP) Status update (heartbeat) connection from E SXi to vCenter Server |
| ESXi 5.x | 1024 (dynamic) | TCP/UDP | ESXi Host | Active Directory Server | Bi-directional communication on TCP/UDP ports is required between the ESXi host and the Active Directory Domain Controller (via the netlogond process on the ESXi host). See Active Directory and Active Directory Domain Services Port Requirements and MS article 179442. |
| ESXi 5.x | 2049 | TCP | ESXi 5.x | NFS Server | Transactions from NFS storage devices |
| ESXi 5.x | 2049 | UDP | ESXi 5.x | NFS Server | Transactions from NFS storage devices |
| ESXi 5.x | 3260 | TCP | ESXi 5.x | iSCSI storage server | Transactions to iSCSI storage devices |
| ESXi 5.x | 5900 to 5964 | TCP | ESXi 5.x | ESXi 5.x | RFB protocol, which is used by management tools such as VNC |
| ESXi 5.x | 5988 | TCP | CIM Server | ESXi 5.x | CIM transactions over HTTP |
| ESXi 5.x | 5989 | TCP | vCenter Server | ESXi 5.x | CIM XML transactions over HTTPS |
| ESXi 5.x | 5989 | TCP | ESXi 5.x | vCenter Server | CIM XML transactions over HTTPS |
| ESXi 5.x | 8000 | TCP | ESXi 5.x (VM Target) | ESXi 5.x (VM Source) | Requests from vMotion |
| ESXi 5.x | 8000 | TCP | ESXi 5.x (VM Source) | ESXi 5.x (VM Target) | Requests from vMotion |
| ESXi 5.x | 8100 | TCP/UDP | ESXi 5.x | ESXi 5.x | Traffic between hosts for vSphere Fault Tolerance (FT) |
| ESXi 5.x | 8182 | TCP/UDP | ESXi 5.x | ESXi 5.x | Traffic between hosts for vSphere High Availability (vSphere HA) |
| ESXi 5.x | 8200 | TCP/UDP | ESXi 5.x | ESXi 5.x | Traffic between hosts for vSphere Fault Tolerance (FT) |
| ESXi 5.x | 8301 | UDP | ESXi 5.x | ESXi 5.x | DVS Port Information |
| ESXi 5.x | 8302 | UDP | ESXi 5.x | ESXi 5.x | DVS Port Information |
| ESXi 5.x | 31100 | TCP | vCenter | SPS Server | Internal Communication Port |
| ESXi 5.x | 31000 | TCP | SPS Server | vCenter | Internal Communication Port |