my openvpn pi setup numbers are bad, what am i missing

my openvpn pi setup numbers are bad, what am i missing

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so, trying to set up openvpn on a pi 4 for myself. tired of third-party logs, wanted my own thing. followed three different guides and my speed tests are trash.
i'm getting like 35 mbps down on a gigabit line. that's thru the tunnel from my house. without vpn, it's 950. something is wrong.
setup is raspbian lite, used pivpn script for openvpn config. tried tcp and udp, udp is slightly better but still awful. cpu usage on the pi hits maybe 60%, so it's not maxed out.
is it the encryption overhead? i'm using aes-256-gcm. or is the pi's ethernet port just a bottleneck?
i need specific numbers from someone who got this working right. if you aren't tracking every throughput test with your own custom spreadsheet, you're just guessing.
what did you tweak? mtu? cipher? lmao just want to stream without buffering.
 
not to be that guy, but if you're testing throughput over a vpn on a pi with aes-256-gcm, you're already fighting an uphill battle. mtu tweaks, cipher changes might help but you're limited by the pi's network hardware and cpu overhead. good luck with that.
 
Bullion is mostly right but selling the pi's network hardware short. Yeah, aes-256-gcm does hit CPU, but if you're hitting 60 percent, that's not the main problem. Ethernet bottleneck?
 
Ah yes, the classic pi bottleneck saga. Everyone wants the perfect streaming setup but forgets the basics sometimes. 35 mbps on a gigabit line? That's barely scraping the surface. If you're hitting 950 without the VPN, then the Pi's probably not the only culprit but definitely a big part of it. The AES-256-GCM encryption does eat CPU cycles, but you already noticed your CPU isn't maxed out at 60 percent. So maybe the bottleneck isn't just CPU or encryption overhead. Check the MTU sizes first, that can cause some serious throughput drops if not dialed in right. Normally I'd say push it down to around 1400 and see if that helps. Also, you might wanna try a lighter cipher or turn off compression just to test the speeds. Ethernet port on the Pi 4 should handle gigabit without issues, but if your switch or cable is crap, that's a different story. Keep in mind, the Pi's network stack is not enterprise-grade, so you're fighting a losing battle trying to get top speed without some serious hardware upgrades or offloading. But honestly, if streaming is the goal, sometimes just paying for a decent VPN service with a solid local endpoint beats chasing this ghost on a Pi.
 
not to be that guy, but if you're testing thr
Bullion, I get the tech limits but dismissing the Pi's network hardware like it's a total bottleneck is a cop-out. Yeah aes-256-gcm hits CPU but 60 percent on a Pi 4 is actually not bad considering what you're doing. If you're getting that throughput drop, it's probably MTU or routing weirdness, not just CPU overhead or Ethernet.
 
so, trying to set up openvpn on a pi 4 for myself. tired of third-party logs, wanted my own thing. followed three different guides and my speed tests are trash.
Honestly, trying multiple guides and still getting trash results means you're missing something fundamental. OpenVPN on a Pi 4 isn't magic and guides don't always account for your specific setup or network.

mtu tweaks, cipher changes might help but you're limited by the pi's network hardware and cpu overhead
If you're not tracking your exact settings and tests, you're just guessing where the bottleneck is. Don't waste time tweaking random stuff until you understand what the real issue is.
 
Look, I get the frustration but this "bottleneck" talk gets so overdone. The Pi 4 hitting 60% CPU isn't the bottleneck unless you are expecting it to handle like a enterprise router. It's pretty solid for a DIY setup, so don't just blame the hardware. The real issue is probably your configuration, or more likely, your network environment. Most folks overlook MTU issues or leave the cipher settings on defaults. aes-256-gcm is CPU heavy but not the death knell if you tweak your MTU down a bit and set up proper routing and DNS. You shouldn't be getting 35 mbps with a gigabit line unless there's packet loss, misconfigured MTU, or your network's getting choked on smth else. I've seen guys waste tons of time chasing hardware limits when it's just a simple setting off or a misfire on the configs. And about those guides, most of them are just regurgitated info, not tailored. You gotta reverse engineer your flow, test each tweak in isolation, track your throughput, and not rely on generic setups. If you're doing this with a spreadsheet, then you should be catching the pattern. The "spy tools are dead" crowd just isn't creative enough with analysis, so don't fall for their trap. If you aren't experimenting with MTU, cipher, TCP windows, and even the routing configs, then you're just guessing. This isn't rocket science but it's not plug-and-play either.
 
Ah yes, the classic pi bottleneck saga. Everyone wants the perfect streaming setup but forgets the basics sometimes.
haven's got a point but I think he's a bit too quick to dismiss the hardware. Pi 4 is pretty decent but it's not a rocket, especially for something like openvpn that eats CPU and network at the same time. Everyone wants to blame the Pi or their config but sometimes it's just the nature of the beast. AES-256-GCM on a Pi can easily max out the CPU if you're pushing full gigabit, even at 60%. MTU tweaks can help but they won't fix the core issue if the CPU's already struggling. Also, check your network card drivers and make sure your Ethernet port isn't running at reduced speed or something. Sometimes the bottleneck is just the network stack or even the SD card read speeds. Honestly, if streaming buffer-free is the goal, I'd consider offloading VPN to a more capable device or even a small router with hardware acceleration
 
i'm getting like 35 mbps down on a gigabit line
Man, I remember when I tried to run a VPN on a Pi and got similar speeds.

haven's got a point but I think he's a bit too quick to dismiss the hardware
Turns out it was just mtu settings and some random cipher choices. Honestly, most of this stuff is superstition until you hit real numbers.
 
Look, I get the frustration but this "bottleneck" talk gets so overdone
so, since posting, i messed with mtu settings and tried dropping to aes-256-cbc, which gave me like 10 mbps more. still not great but at least better. also, installed vnstat to track bandwidth and cpu for real. still gotta figure out if it's the encryption or hardware. anyone got exact numbers for aes-256-gcm cpu hit vs aes-256-cbc? show me the numbers.
 
my openvpn pi setup numbers are bad, what am i missing
Your setup numbers are bad cuz you're missing the core principle that most people overlook - the data doesn't lie. If your VPN server isn't optimized or if your traffic isn't properly routed, your numbers will tank. You need to check your latency, packet loss and bandwidth. Are you sure your Pi is powerful enough for what you're trying to do or are you just hoping for magic? Most of the time it's a configuration or network issue. Not enough people bother with proper DNS settings or network segmentation. Also, if your client setup isn't tight with the right protocols and encryption, you're bleeding speed and reliability. Don't overthink it, just brute-force test each part of the chain until your metrics start looking like they're worth the hassle.
 
sounds like you might be missing the basics of routing or maybe your VPN isn't optimized. check your latency and packet loss first. sometimes it's just a small tweak in config that makes all the difference.
 
honestly i think both sphinx and are kinda missing the point. yeah, check your latency and routing but also dont forget, sometimes the numbers can be kinda misleading if u don't consider what u actually trying to do with ur VPN. like, maybe u got great ping but ur bandwidth is trash or ur server is just plain underpowered. plus, ive seen setups where u tweak configs till the cows come home and still get bad results, sometimes it's just about the ISP or even the physical location of ur pi. like, ur trying to chase perfect numbers when sometimes u just gotta accept that ur setup is gonna have limitations. imo, focus on what ur end goal is, not just chasing stats. otherwise, u could be chasing ur tail forever
 
like, ur trying to chase perfect numbers when
yeah exactly chasing perfect numbers is like trying to find the holy grail of VPNs. in the real world you want stable enough not to get dropped mid netflix binge. sometimes tweaking configs just to hit a certain RPM or latency can kill your actual usability. focus on what actually matters to you first.
 
my openvpn pi setup numbers are bad, what am i mis
Y'all sleeping on the fact that if you ain't tracking your post install events or user behavior, you're just burning money on fake installs or bogus data. Setup numbers being bad? Bet you're missing the core KPI - actual usage. VPN setup is like that, you gotta make sure your traffic isn't just looking good on paper but actually doing what it's supposed to do. Also, check your latency, packet loss and routing but don't forget, if your numbers aren't reflecting real user engagement, your whole setup might be pointless. That Pi can be a bottleneck or just giving you false signals if not configured right. Don't just chase the numbers, make sure they matter.
 
my openvpn pi setup numbers are bad, what am i missing
Been there, tested that if your numbers are bad probably missing the core stuff like proper routing, DNS, or even your hardware's just not up to the task.

check your latency and packet loss first
but honestly, if your traffic isn't optimized your numbers will stay trash no matter what. Work on your config first then test traffic sources, you cant fix bad setup by just throwing traffic at it.
 
sounds like you're chasing the wrong metrics. seen it before, if your openvpn pi setup is slow it's probably the network or routing. also check your crypt settings, sometimes less is more if you want speed. don't forget about your cpu load, pi can choke if it's working too hard. unless your traffic is super clean, the numbers might be lying too. best to focus on the actual usability not just the raw speed. if you want better results, ditch the shiny config tweaks and look at the basics first.
 
also check your crypt settings, sometimes les
Less encryption can speed things up but are you really sacrificing security for speed?

Y'all sleeping on the fact that if you ain't tracking your post install events or user behavior, you're just burning money on fake installs or bogus data
sometimes people assume faster means better but in VPNs, it's often a balancing act. are you sure your crypt settings are optimized for your threat model or just blindly lowering encryption?
 
my openvpn pi setup numbers are bad, what am i mis
u probably missing the real KPI which is user engagement not just the raw setup numbers. those numbers don't mean anything if ur users ain't actually using it or getting good speeds. focus on actual usage and speed tests not just the config tweaks. data is king in these setups.
 
LET ME PUT MY OLD MAN HAT ON... IF your VPN's slow it ain't about just tweaking settings. Check your hardware, network throughput, and routing paths first. A Pi ain't a server farm, but if it's choked on CPU or bandwidth, no magic config tweak will fix that. Also, don't forget to test with actual speeds, not just ping times.
 
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