Hey everyone! I'm dealing with a frustrating issue regarding our Kerio Control setup at work. It's installed on a Hyper-V VM, and typically everything ran smoothly. However, we're now seeing unusually high ping times. The odd thing is, when I disable the internet interfaces, the ping returns to normal, and there's no noticeable CPU, RAM, or hard drive strain, nor any abnormal network load detected. I also checked the ping to the Hypervisor and other VMs, and they all seem fine—it's specifically a problem with Kerio.
I've tried restarting the switches, router, and even Kerio itself, but the high ping persists. I managed to capture some traffic data and noticed there are a lot of TCP Duplicate ACKs and retransmissions, but I doubt this is the root of the issue since I've seen those in previous configurations where everything functioned well. Any thoughts on what might be causing this? I'm really stumped!
3 Answers
I can't provide a direct solution, but I've had a terrible experience with Kerio in the past. One client switched to Fortigate, and they've been really happy ever since. You might want to consider other options like PfSense for a free alternative or Fortigate/Sophos for something paid. Just a suggestion!
Just to clarify, are you seeing the high ping from the Kerio box itself or just high latency with things happening on it or beyond? That’s an important distinction to make.
Looks like those duplicate ACKs might not be the main issue, especially if you're capturing traffic from multiple interfaces. Double-check where the high round-trip times (RTT) are coming from. Also, try running a traceroute; that can really help you identify where the delay is happening. Good luck!
Thanks for the advice! I did a traceroute, and the RTT is high from both clients and servers to the VM where Kerio is deployed. The network's pretty simple, just one router, but I'm still seeing high ping even within the same network.
I appreciate the suggestion, but switching from Kerio to PfSense or similar isn’t an option for us right now.