Rack mount servers tend to be in a different class than most tower servers. There used to be little difference between PCs and servers when tower cases were more common years ago. These days desktop PCs and laptops are more common but tower servers remain. The advantage is more space for drives and expansion boards.
I had a chance to check out Super Micro Computer's (SuperMicro) AS-4022G-6F A+ Server (Fig. 1) to see what the latest high performance servers look like and how it differs from a tower-based PC.
The AS-4022G-6F system is designed for AMD processors including the latest Opteron 6000 Series. These chips top out with 16-cores right now.
The high performance processors needs good support too. The system has eight hot-swap, 3.5-in SAS/SATA drive bays. It also has lots of cooling capacity and a high performance power supply. A second, redundant power supply is optional. There is even a dedicated, Ethernet IPMI v2.0 interface that is typical of rack mount systems but rare in tower systems. Of course, the system can be rack mounted as well. Here are the system's basic specs.
AS-4022G-6F A+ Server Specs
- Tower / 4U rack mountable
- Dual 1944-pin Socket G34
- Supports up to two 16/12/8-Core ready AMD Opteron 6000 Series processors
- HT3.0 Link support
- AMD chipset SR5690 / SP5100
- 16 DIMM sockets
- Up to 256GB DDR3 1600/1333/1066 MHz memory or 64 GB of DDR3 Unbuffered ECC/non-ECC
- Quad channel memory bus
- DDR3 1600/1333/1066 MHz Registered ECC Unbuffered ECC/non-ECC SDRAM 72-bit, 240-pin gold-plated DIMMs
- 1GB, 2GB, 4GB, 8GB, 16GB
- 1.35V or 1.5V
- ECC corrects single-bit errors, detects double-bit errors
- AMD SP5100 (RAID 0, 1, 10)
- LSI 2008 SAS2 (RAID 0, 1, 10, 5)
- (Optional) AOC-SAS2-RAID5-KEY: RAID 5 support
- 8 hot-swap 3.5-in SAS/SATA drive bays
- Intelligent Platform Management Interface v.2.0
- IPMI 2.0 with virtual media over LAN and KVM over LAN support
- Implemented via Winbond WPCM450 BMC
- Dedicated IPMI Ethernet port
- Intel 82576 controller, dual-port Gigabit Ethernet
- 10/100/1000BASE-T support
- Matrox G200eW 16M bytes DDR2
- 3 x16 slots
- 1 x8 slots
- 2 x4 slots
- 8 USB 2.0 ports
- DB9 serial port
- PS/2 keyboard and mouse
- 16 Mbit Flash EEPROM with AMI BIOS
- Plug and Play (PnP)
- APM 1.2
- DMI 2.3
- PCI 2.2
- ACPI 2.0
- BIOS Rescue Hot Keys
- USB Keyboard Support
- Hardware BIOS Virus Protection
- SMBIOS 2.3
- 920W high-efficiency (94+%) power supply with PMBus and power distributor
- 5 fans, 80x38mm with 4-pin PWM
- Thermal control for 8x fan connectors
- I2C temperature sensing logic
The H8DG6-F motherboard (Fig. 2) is just one option for the case. It handles a pair of AMD Opteron processors including th 16-core 6000 Series processors I used to check out the system. The motherboard has six PCI Express slots including three x16 slots that would be ideal for GPUs providing even more processing power than two Opteron processors.
The motherboard already has an optional LSI 2008 SAS RAID controller chip so an additional PCI Express RAID controller is only needed if an additional storage system is going to be attached. It will handle 6 Gbit/s drives in the hot-swap array but newer 12 Gbit/s SAS drives would require a newer controller if the need for speed is there. As is, the LSI option is likely to deliver more than enough performance for a standalone system.
The IPMI support is another thing that really impressed me. This motherboard will work in other rack mount systems so it is not surprising that the IPMI support is one of the options. The system uses the Winbond WPCM450 BMC (baseboard management controller). This incorporates a Matrox G200eW video controller in addition to the usual Ethernet-based IPMI support. This means a headless system can be easily managed using an Ethernet connection. The graphics interface can be accessed remotely.
Of course, IPMI provides complete, remote management of the system. This means I could update the BIOS and was able to track system status like fan speeds and temperatures and much more. Enterprise users of SuperMicro's hardware will be very familiar with this feature already but it tends to be less known in the small business market where this type of system is often found.
The motherboard provides a lot of flexibility for a server. It can handle 256 Gbytes of registered ECC DDR3 memory. Lower cost unbuffered DDR3 memory limits capacity to only 64 Gbytes. The system can use unbuffered ECC and non-ECC memory.
The inside of the system (Fig. 3) highlights SuperMicro's advanced design that puts it on par with the more rugged, rack mount systems. The plastic, removable air shroud concentrates cooling air around the processor heatsinks and over the DRAM. The system has a push-pull architecture with a set of internal fans and two on the rear of the system.
The internal fans pull air through the 8 hot swap drive bays. Some of the fans direct air through the processor/RAM area covered by the shroud. The others push air past any installed adapter cards. All the fans snap out. No playing with power cables here.
One thing the fans do not cool is the hot swap power supply. The power supply has its own cooling fan but it is only for the power supply. Conventional PC power supplies normally cool the system as well. Of course, swapping aspect is only usable if two power supplies are installed. This feature requires power distributor not found on most PC systems. The power supplies have a PMBus interface that allowed me to track its operation using the IPMI system.
A closer look at the hot swap bays is worthwhile since I was using 2.5-in drives. This included five Seagate 15K Savvio drives (see Family Of Drives Span Enterprise Storage Needs) and a pair of Micron P300 flash drives (see Building A Hybrid RAID NAS Server). These are enterprise drives. I will not cover it in detail here but these will be used in conjunction with LSI's CacheCade software. CacheCade will use the flash drives as cache for the SAS hard drive array.
The 2.5-in drives need an adapter to fit into the 3.5-in drive bays (Fig. 4). This type of adapter is common but it is interesting to note how the smaller drives fit into the trays because the hard drive connectors need to line up properly. This means that the drive is bolted onto the tray on one side and the adapter on the other. Likewise, the Micron P300 flash drives are thinner than the full height Savvio drives and need a standoff for proper alignment.
A 2U rack mount system might be a better combination if viewed from the drive standpoint. On the other hand, if a trio of GPU boards other other adapters are required for an application then this system makes more sense. Any combination of 2.5- and 3.5-in drives can be supported by the system.
The three 5.25-in drive bays might get some use if a tape drive or optical storage drive is required. I suspect most systems will not use these drive bays.
Bottom line, from a design standpoint, this system is the best around. Power, fans and drives are hot swappable and you have 32 cores when using a pair of the latest, top end Opterons. It is the system balance that makes a difference and the LSI SAS RAID subsystem plus three x16 PCI Express slots are a great match. The remote management allows it to work equally well in a remote office or in a lights out, rack system.
That's it for the hands-on view of the hardware. The software article will take a look at features like the IPMI support and LSI CacheCade operation along with using the system with some applications like Hadoop.
The link to the software side of this article will be added once it is posted.