Interesting, how were you able to exceed the 600 Mbps hard limit by such a significant amount? Also very surprised to see that you are seeing higher throughput numbers with security enabled vs. disabled, that doesn't seem to make sense. Either way, I re-tested again tonight and discovered that right after a reboot, I get 600 Mbps even with security features enabled. Some period of time later after doing some minimal browsing and cellular testing, I tried the speedtest again and I'm back to down to 275 Mbps. No change in the WAN connection, if I take the uplink cable out of the MX and plug it into laptop I get 1 Gbps. I rebooted the MX again and speeds went back up to 600 Mbps. Fortunately none of the sites I'll be deploying MX 17.6 to have anything greater than 200 Mbps so not an issue for now. Perhaps I'll just wait and see if this resolves as MX 17.x matures. Side note: each time I reboot the MX67C, when it comes back online it starts out on cellular for about 30 seconds (status light purple and confirmed via tracert) before switching to wired uplink.
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