Server Hardware Cheatsheet

Server Hardware Cheatsheet

Form factors, IPMI, ECC RAM, and redundancy at a glance.

Form Factors
1U (44 mm) Dense rack servers ߀” quiet, power-efficient, limited drive bays
2U (88 mm) General purpose ߀” good balance of drives, expansion, and density
4U (176 mm) Storage servers, GPU compute, large drive counts
Tower Small offices; same hardware as rack but in a tower chassis
Blade High-density shared chassis ߀” shared power and networking backplane
Remote Management
IPMI Generic standard (Supermicro, generic); web UI + IPMI tool CLI
iDRAC Dell ߀” iDRAC9 on 14th gen+; full KVM, virtual media, power control
iLO HPE ߀” iLO5/iLO6; equivalent to iDRAC with HP-specific features
XCC Lenovo ThinkSystem ߀” Lenovo XClarity Controller
Default IP Usually on a sticker on the server; default credentials in manual
ECC RAM Types
UDIMM ECC Unbuffered ECC ߀” workstations; not supported on all server platforms
RDIMM Registered DIMM ߀” standard server ECC RAM; required for high capacity configs
LRDIMM Load-Reduced DIMM ߀” allows maximum capacity (e.g. 1.5 TB/socket); slightly higher latency
NVDIMM Non-Volatile DIMM ߀” battery-backed; survives power loss; used for persistent memory
Redundancy
Redundant PSU Two PSUs in load-sharing mode ߀” connect to separate circuits
Hot-swap drives Replace failed drives without shutting down (RAID required)
Dual-port NIC Two network ports ߀” one fails, traffic moves to the other (bonding/LACP)
UPS Uninterruptible Power Supply ߀” battery backup for graceful shutdown on power loss