jllawler
Hi. I'm a long time OpenVPN user (5+ years at least), and I love the product. It's typically one of those set it and forget it kind of products that just fades into the background. I usually have a little trouble getting started on a new platform with it, but I've left a couple of production servers alone at two business locations and they just work great for our uses.
I'm posting today because starting (I think) this past Saturday morning I started experiencing ridiculously poor performance over my OpenVPN client connection to these two *separate* OpenVPN servers, both of which are hosted on entirely independent DSL connections.
My client is running on a PC running pfSense 2.0.1-RELEASE, which I've been using for several months at least, and has been running very smoothly.
My general Comcast connection seems unaffected by these problems, regular web browsing seems to go more or less without a hitch, regular web based speed tests seem to come out about the specs of the connection.
But *any* traffic that I run over the two VPNs seems to slow to a crawl, even pings will frequently time out, or just take much longer to come back than they normally would. I try to copy a 90kb file from a remote location to me and it takes many minutes or times out instead of taking 5-10s like it normally would.
I finally called Comcast last night to report the issue to see whether any known problem was around, and of course the CS person was not aware of any. He asked me to test a direct connection to the modem (bypassing the router) to see if I could duplicate the situation there. I didn't get to that until this morning, and sure enough, bypassing the pfSense setup, I see the *exact* same problem when using WinXP directly connected to the modem, and OpenVPN GUI running on Windows to the same servers. If I get off of that connection and switch to a Verizon wireless 4G connection, picked up on the WinXP via WiFi and again connect to the VPN, guess what? No problem with latency, just like at other sites that are using different internet connections to connect to these OpenVPN servers.
I do have one report of another Comcast client in the same area connecting and apparently having no problems, but there is one other Comcast client in the area that seems to be having similar general latency problems.
I mostly wanted to post for advice from other users, to get this report out there in case it's something serious going on (I tend to blame myself for these problems, but from what I can tell, I've done all reasonable testing and it points to Comcast, no where else), and get any other testing / troubleshooting steps I can take.
Thanks for your attention and expertise.
jllawler
I should also mention that I have run one of the OpenVPN clients at fairly high logging verbosity and watched that log. I saw nothing unusual (no ERROR or dropped packet kind of messages that looked suspicious), so I counted that one as a dead end for now.
nickfank
I don't have a solution for you, but I'd like to compare symptoms. I have two connections available- one through BridgeMaxx & one through a small local provider. When I'm using my local ISP, OpenVPN works fine. When I switch to the BridgeMaxx connection, Open VPN negotiates a connection with no problem, and as long as I'm moving very small amounts of data, I'm fine, but if I try to do a long directory listing or transfer a large file, the connection times out. I theorize that it's happening whenever more than one packet is required.
The Comcast tie-in is that a coworker is experiencing similar problems with a Comcast connection, but coworkers using several other ISPs are having no problem. We're trying to puzzle out what Comcast & BridgeMaxx have in common about their networks that might cause this.
jllawler
Hmm. Interesting -- I don't have any specific insights to the situation you're describing but I've been meaning to post an update to my situation for a couple of days, so I'm glad you posted to remind me to do this.
A co-worker of mine in the same area (central Illinois) was experiencing very close to the same problem (his symptoms seemed to affect *all* of his Comcast connection, not just traffic through his OpenVPN connection to one of the same servers I was experiencing trouble with).
He theorized if we could somehow get Comcast's DHCP servers to kick our connections over to a difference range of IPs, we might find that the problem goes away because only a certain range was affected. His idea was to just spoof the MAC address of our routers, then reset the modem and see if that change in MAC causes a re-allocation to a different DHCP IP.
I haven't yet heard back from him as to whether that solved his problem, but the very first time I tried that, I (luckily) got moved to a completely different range of IPs (in the A.B.C.D addresses, the C part changed, at least), and this immediately seemed to solve my problem.
So I haven't fussed with it any more because it's working great, but if you can try the same thing on your problem network, you might give it a shot.
