This one racked my brain quite a bit, so I hope you enjoy the solution
The Problem
My problem is that I wanted to play nice with other people’s time servers. I have a small local network, and at any time I can have 5 devices (2 routers, up to 3 computers) that will want to synchronize their clocks with a time server. I could sick them all on one time server, but that might verge on me getting an IP ban. (NTP’s minimum of 64 seconds between queries / 5 machines = me hitting a server every 21 seconds on average.) I could pull from a pool, but every computer might “jitter” as they’re pulling their time from all over the country.
The Solution
The solution in this case is to set up your own NTP server that synchronizes with another server over the internet, and then have all the machines on your local network poll that machine. HOWEVER, if you’re using cable broadband, your ISP is most likely blocking anyone from accessing ports below 1024. I’m sure some DSL providers do so as well, but the rule of thumb goes that cable providers block access while DSL providers do not.
Well, that just throws a wrench in our gears, no doesn’t it? Well, it doesn’t have to. There’s another solution if time synchronization isn’t overly critical.
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