diaboliX.org

1 Mac mini (early 2009) as a Server (part 1)

Adding a second hard disk for RAID-1 Redundancy

 

The advantage of the Mac mini as a server is, without doubt, the low power consumption in comparison to a Mac Pro or a XServe. We don’t even want to talk about the price.

For sure, the reliability is by far not equal to a Mac Pro. Nevertheless, in a small office or home office it is good enough. That’s why I have chosen this hardware for my two servers.

 

 

1.1 Redundancy

I have connected several RAID-5 Mass Storage Units through FireWire 800 providing a capacity of 3 Tbyte in addition to a Time-Machine Backup also configured as RAID-5. So finally the 8 disks each with 1 Tbyte of capacity “only” provide 3 Tbyte of usable storage. I do not worry about data loss on those devices.

On the other hand, the operating system (Mac OS X Server 10.5) installed on the internal 120 Gbyte drive is not perfectly “save” in case of a hard disk crash. That’s why I decided to change this by adding another internal SATA hard disk with the same specs as the original.

1.2 Adding a second 2.5″ SATA disk

For this purpose I will need to remove the optical drive and find a way to attach the second drive to the slim SATA port and power. After finding a proper way on how to accomplish that, I wanted to find out if this hardware change in the Mac mini enclosure adds more redundancy in reality.

1.2.1 The concerns by adding another 2.5″ hard disk:

1. The power consumption of the whole system is out of the specs
2. The air flow in the Mac mini case is not working properly anymore and heating up the complete system
3. The heat produced by the second hard disk is adding too much additional heat to the components

1.2.2 The results by calculating the figures:

1. Power: The two drives have the following specs: 1.8W read/write power and 0.55W low power idle. Combined they are using up to 3.6W. Now let’s compare this with the built in optical drive. 2.5W read/write and 0.12W idle. Conclusion: no problem!
2. Air Flow: Due to the construction inside the Mac mini (early 2009), the airflow is running through pipes and other constructions made of plastic. The SuperDrive is an important part for the air flow design which transports the heat away from the CPU and other heat producing components. Conclusion: I need to build some parts (maybe from plastic) to keep the air circulating like it was constructed by Apple!
3. Heat: This needs to be carefully measured. If the temperature on one of the heat sensors is raising higher than before the hardware change, everything needs to be checked again. Here are the details of the current heat situation in the enclosure:

This entry was posted on Saturday, May 23rd, 2009 at 2:30 am and is filed under Mac Hardware, Mac OS X Server. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.