Just to provide an update on this issue.
There is definitely an issue with the sync software. It just does not work. After many hours, days of waiting, the sync failed with the Degraded message. These are brand new drives. The first, I bought 2 months ago when I bought the DNS-323, the second I bought last Friday. They are identical drives:
1. WDC WD10EAVS-00D7B0 WD-WCAU48420562 1000 G
2, WDC WD10EADS-00L5B1 WD-WCAU4C543991 1000 G
Second of all, I would like to put out a strong warning to anyone who is trying to let DNS-323 format a new drive with another drive having data you cannot afford to lose. Make sure you have a good backup copy of all your data somewhere else! The following is why:
In the process of trying to get RAID 1 working, and after discovering the sync failed. I took out the new drive and delete the partition while confirming that the existing drive is till good. After performing the partition deletion (there are 3 partitions), I re-install the drive into DNS-323. It detected the newly inserted drive and offer to format it in order to re-establish RAID 1. I click next to go ahead. It shows me the new drive to be formated, I notice the serial number was wrong since I have been taking notes. It actually asked me to format the dirve with good data. So I click the back button. Boom! It started formating!
That is crazy! The back button started the formating process! I ended up losing all data. Fortunately, I do have a full backup stored some where else, whew. After the format completed, for the first time, after reboot, it shows what I want to see RAID 1 - no more sync. The format appeared to have worked but at the expense of losing all data in the drive it was not supposed to format.
The moral, don't trust the fomat operation, always have a good backup.
Hope this help someone else to avoid a disaster.