My Situation with DAS vs NAS
Being an Wi-Fi and Network professional I’d like to think I know everything about how things in IT work. The truth is, no one knows everything. I was getting into Adobe Lightroom and I had about 100k photos that I need to move from Aperture into Lightroom. I wasn’t really organized in Aperture, so organization was going to be key for me. In order to do this, I also wanted to have all of my photos on redundant disks and backed up. The focus of this post is to explain DAS vs NAS solutions and making Adobe Lightroom fast! I am hoping others can learn from my mistakes.
I knew I needed RAID5 or RAID6 for storage with speed and I wanted my storage to be NETWORK accessible, over my Wi-Fi network specifically. RAID5 and RAID6 give you multiple disks which provide some redundancy within the system. I really wanted to have all of my photos stored on a central Network Attached Storage (NAS) box and I could use my laptop to find, browse, edit, or tag all of them from anywhere in the house. Then the NAS would automatically sync and perform my offsite backup. Technology wise, all of this should be easy to do when you understand the tools available. The catch was, I didn’t know exactly how Lightroom worked. I listened to professional photographers and Lightroom experts talk about brands like Drobo, Synology, Promise Pegasus and others that make both NAS (Network Attached Storage) and DAS (Directly Attached Storage) arrays. They never distinguish between the two, but sometimes they say “NAS”. What I learned was they really meant DAS! The connectivity to your work station needs to be Thunderbolt or USB3.
DAS vs NAS – Understanding the problems
I spent about 1 year going down the path of having the catalog stored on a laptop and then the photos stored on the NAS. I would always end up frustrated and angry with the performance. Then one day I was watching a video on Lightroom and it clicked, they said “You need to have all of your photos on 1 single directly attached drive”. I went back and referenced Duncan Fawkes document on using a NAS with Lightroom and it all made more sense.
Lightroom is an extremely chatty program with your disk. Searching for files, writing .XMP files, pulling up a single file at a time. All of this requires read/write speeds that are almost exclusively available only via directly attached disks. SSD is the best solution, but storage on these is limited. So your next best solution is a DAS RAID array.
DAS won the DAS vs NAS fight for me. I use the Pegasus R6 from Promise Technologies; however, there are several other options that work just as well. Here is a link to the latest version of it, you can size it to your needs.
After all of my images were organized on the Promise, I could start use my laptop as a mobile device. But my work flow looks like this from a storage stand point.
- All new image go onto the Mac Book Pro’s SSD drives directly, I keep about 3 months of RAW images here
- All images after 3 months go onto the Pegasus for storage / archival
- Every Monday I run a back up script to sync all of the Mac Book Pro’s files over to my NAS
- Every Tuesday I run a back up script to sync the Pegasus Files to my NAS
- My Mac Mini copies everything from the NAS the following day and gets everything up to Backblaze (which I highly recommend for offsite backups!)
This more or less follows Duncan’s diagrams and works great for me. The difference is I can disconnect the Pegasus and fully use my Mac Book Air around the house or wherever with the last 3 months of files on it. I keep a folder on it for my favorite images for quick references.
Ask Questions if you need help
I hope this helps. If you have questions around the topic of DAS vs NAS, ask and I will do my best to answer them. I hope to do a follow article to recommend specific DAS and DAS hardware for different budgets, let me know if this is interesting to you.