To determine how much RAM is installed in each slot on an ESX/ESXi host:
Login to the host using an SSH client.
Run one of these commands as user root:
dmidecode|less
Note: dmidecode|less is not available in 5.x versions.
smbiosDump
In the output, locate the blocks of text beginning with Memory Device. Size or Max. Size indicates the amount of memory installed.
The output for slots that have memory modules installed appears similar to:
Memory Device Array Handle: 0x1000 Error Information Handle: Not Provided Total Width: 72 bits Data Width: 64 bits Size: 4096 MB Form Factor: DIMM Set: 1 Locator: DIMM_A1 Bank Locator: Not Specified Type: <OUT OF SPEC> Type Detail: Synchronous Speed: 1333 MHz (0.8 ns) Manufacturer: 80AD009780AD Serial Number: 1680125F Asset Tag: 0109241D Part Number: HMT151R7AFP4C-H9
The output for slots that are empty appears similar to:
Memory Device Array Handle: 0x1000 Error Information Handle: Not Provided Total Width: 72 bits Data Width: 64 bits Size: No Module Installed Form Factor: DIMM Set: 2 Locator: DIMM_A4 Bank Locator: Not Specified Type: <OUT OF SPEC> Type Detail: Synchronous Speed: Unknown Manufacturer: Serial Number: Asset Tag: Part Number:
Additional Information
Check with your server vendor for compatibility prior to adding any new memory modules.