I know the DNS-321 has been phased out, but there will be a lot of them out there for a few years, so I am passing this on.
I own eight D-Link NASs on a GB Network. All are running RAID 1 and are either 1TB or 1.5TB. Four are DNS-321 and four are DNS-323. A few weeks ago I discovered that a drive in one of the units had failed by luck: I stumbled into it while doing something else. Fortunately, there was no harm done with the drive failure and Western Digital was nice enough to replace the drive. Feeling dumb about this, I decided to set up the NASs for email notification so I would not have to stumble into a drive failure. Here is where the fun started.
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My ISP is Cox Cable. I have set up countless applications and devices to send emails on Cox. These DNS-321's defied my best efforts. I double checked everything, even the Gateway IP and the DNS IP. I even used the IP for the Cox SMTP URL, just in case there was a DNS issue. The result was failure after failure.
I took a day off to let my brain settle. I then tried setting up a DNS-323. All the important settings on the 323 are the same as the 321. The 323 has an additional setting for port. I left the port at the default of 25 since that is what the Cox SMTP expects. Everything worked just fine! I repeated this on the other three 323's and all sent emails with no problems.
I remembered something I had read about using gmail for DNS-321's, so I experimented with one of the 321's using my gmail info. Wah-Hoo, it worked. It worked on all four DNS-321's so I set up my gmail account to auto-forward those emails to my Cox account. What a fire drill! The problem is not with Cox Cable nor with my ability to put the correct numbers in the correct spaces. The problem is with the DNS-321. Whatever is broken in the DNS-321 will stay broken since it is obsolete, but this is my work-around.
I thought I would pass this info on since there are quite a few DNS-321's out there.
Have a good day.
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