Today I had a request from our user for add a PCIe SSD card to a server. One option is you walk to this server and open it. This not the best option to check if it a PCIe slot available.
Another option is use your Linux commandline.
You need your server mainboard manual to see which slot is labeled.
You have only to check under current usage is in use or available.
Current Usage: Available
dmidecode -t 9
# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 3.2.1 present.
# SMBIOS implementations newer than version 3.2.0 are not
# fully supported by this version of dmidecode.
Handle 0x000B, DMI type 9, 17 bytes
System Slot Information
Designation: CPU1 SLOT2 PCI-E 3.0 X16
Type: x16 PCI Express 3 x16
Current Usage: In Use
Length: Long
ID: 2
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:18:00.0
Handle 0x000C, DMI type 9, 17 bytes
System Slot Information
Designation: CPU1 SLOT4 PCI-E 3.0 X16
Type: x16 PCI Express 3 x16
Current Usage: In Use
Length: Short
ID: 4
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:3b:00.0
Handle 0x000D, DMI type 9, 17 bytes
System Slot Information
Designation: CPU2 SLOT6 PCI-E 3.0 X16
Type: x16 PCI Express 3 x16
Current Usage: In Use
Length: Short
ID: 6
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:86:00.0
Handle 0x000E, DMI type 9, 17 bytes
System Slot Information
Designation: CPU2 SLOT8 PCI-E 3.0 X16
Type: x16 PCI Express 3 x16
Current Usage: In Use
Length: Short
ID: 8
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:af:00.0
Handle 0x000F, DMI type 9, 17 bytes
System Slot Information
Designation: CPU1 SLOT9 PCI-E 3.0 X16
Type: x16 PCI Express 3 x16
Current Usage: Available
Length: Short
ID: 9
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:ff:00.0
Handle 0x0010, DMI type 9, 17 bytes
System Slot Information
Designation: CPU2 SLOT10 PCI-E 3.0 X16
Type: x16 PCI Express 3 x16
Current Usage: Available
Length: Short
ID: 10
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:ff:00.0
Handle 0x0011, DMI type 9, 17 bytes
System Slot Information
Designation: CPU2 SLOT11 PCI-E 3.0 X4(IN X8)
Type: x4 PCI Express 3 x8
Current Usage: Available
Length: Short
ID: 11
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:ff:00.0
Handle 0x0012, DMI type 9, 17 bytes
System Slot Information
Designation: M.2 CONNECTOR
Type: x4 M.2 Socket 2
Current Usage: In Use
Length: Short
Characteristics:
3.3 V is provided
Opening is shared
PME signal is supported
Bus Address: 0000:02:00.0
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User Account Control: Run all administrators in Admin Approval Mode
This affects how UAR works and can block remote local admin connections.
This can be changed in Local Computer Policy | Computer Configuration | Windows Settings | Security Settings | Local Policies | Security Options
Set it to Disabled, requires a reboot