Thanks for the suggestions. I'll try adjusting the MTU and open a TAC case if necessary.
Original Message:
Sent: Jul 03, 2025 10:24 AM
From: willembargeman
Subject: Slow VIA VPN download speeds
Probably lowering the encryption will help. I think the best is to open a TAC case.
One test you can do is a iPerf test with a small packet size.
Default VIA MTU is 1452. Maybe lowering the MTU can help (depends on encryption overhead and path MTU).
------------------------------
Willem Bargeman
Systems Engineer Aruba
ACEX #125
Original Message:
Sent: Jul 03, 2025 09:32 AM
From: jthomassie
Subject: Slow VIA VPN download speeds
iPerf download test to the client results:
Client connected to SDBranch GW 370 Mbits/s (~ 46MB/sec)
Client connected to MicroBranch GW 210 Mbits/s (~ 26MB/sec)
Client connected to VIA 24 Mbits/s (~ 3MB/sec)
Any insight is greatly appreciated!
Original Message:
Sent: Jul 02, 2025 05:17 PM
From: jthomassie
Subject: Slow VIA VPN download speeds
Many thanks for the response.
VIA Clients are UDP connections w/ AES256 encryption.
Initial tests were downloading ~1GB files from an SMB server to the client machine. MB/sec is correct.
Same client machine on the same 1Gb internet connection.
Client behind hardware gateways (SD-Branch 9004 & MicroBranch 505H) provided ~40MB/s downloading the files.
Client connected with VIA VPN provided ~4MB/s downloading the same files.
I plan to retest after production hours to get iPerf results also.
Original Message:
Sent: Jul 02, 2025 08:17 AM
From: willembargeman
Subject: Slow VIA VPN download speeds
How is the client connected? UDP or via the VPN SSL fallback? Hardware gateways will always provide more performance then compared with VIA.
What type of traffic is being used for testing? Do you mean 4MB/sec or 4Mb/sec?
The type of encryption is being used? 150mbps should be possible with VIA.
------------------------------
Willem Bargeman
Systems Engineer Aruba
ACEX #125
Original Message:
Sent: Jul 01, 2025 09:51 AM
From: jthomassie
Subject: Slow VIA VPN download speeds
Hi,
Same problem here also with no bandwidth contracts. Any fix or is this a software limitation?
Hardware gateways connected to the same VPNC get full transfer speeds inside the tunnels while VIA users get ~4MBs to the same servers.
Any pointers are greatly appreciated!
Original Message:
Sent: Apr 19, 2021 04:20 PM
From: pubjohndoe
Subject: Slow VIA VPN download speeds
Nope, I've had TAC case open since I asked it here. TAC just tries to get me to gather all kinds of logs and packet captures but doesn't seem they have much idea what to actually try. VIA client has updated at least once since opening the ticket so it was a new opportunity to get all the previous logs again :) Now I'm supposed to get packet captures but not really sure what is the point in that either...
Seems there has been internally some issues with multicast traffic, as TAC could see 2 packets in a minute capture or something then we had to enable multicast optimizations. I've had the same thing with other tickets too.
From what I can remember we've also tried changing MTU and probably rebootin everything and trying with other device. We haven't tried touching different algorithms on the VPN tunnel itself.
One reason why it takes so long to solve issues like these is that TAC responds 1 minute before their shift ends and no matter how fast I reply I get out of office messages. Then in 1-2 days I'll get "thank you for the logs let me get back to you by the end of business day tomorrow or day after". And then again the next reply comes 1 minute before changing shifts...
Original Message:
Sent: Apr 19, 2021 12:27 PM
From: Cristobal Pastene
Subject: Slow VIA VPN download speeds
Hello, any news about what you report? I have exactly the same problem.
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Cristobal Pastene
Original Message:
Sent: Mar 03, 2021 12:45 PM
From: Jukka Aaltonen
Subject: Slow VIA VPN download speeds
I'm getting only around 30-40% of my availabe bandwidth when using VIA VPN client. Without VPN, and with 303H/505H connected to the exactly same VPNC I can get dowload speeds of around 10MB/s from my lab HTTP server. But with VIA VPN client only around 3-4MB/s.
IAP connection is also within a tunnel but still performs a lot better. And VPN overhead shouldn't be 60-70% :)
Any thoughts? TAC has been working with this for a month or so and they keep asking for new debug files but no progress so far. So maybe someone else has the same issues?
VNPNC is Central managed 7210 with 8.6.0.4, client is the newest one at least the one that was newest few weeks ago (finally working domain pre-connect in this version...)