protonscr

Extremely Slow Download when DNS Failover to Secondary

steamopen duplicateSteam client
ValveSoftware/steam-for-linux#11876 · opened 2025-04-03 by Seqan01 · updated 2025-04-11 · 2 comments · github
SSeqan01 2025-04-03 github

This error seems EXTREMELY specific, so please bear with me

Your system information

  • Steam client version (build number or date): Latest
  • Distribution (e.g. Ubuntu): EndeavourOS
  • Opted into Steam client beta?: No
  • Have you checked for system updates?: Yes
  • GPU: Nvidia RTX 4070

Please describe your issue in as much detail as possible:

For the past several weeks, I have been experiencing slow download speeds on Linux versions of Steam on my local network. Windows was running at 600Mbps while linux was lucky to peak at 50Mbps. I have an engineered network with two local DNS servers and active directories. DNS servers are properly syncing and talking to each other while I work on migrating from one AD to another.

For an unrelated reason, I had to shut down the bare metal where the primary DNS was running. Everything else in the network did not really care aside from slight resolution latency, but Linux Steam clients started downloading at extremely slow speeds.

When I brought the primary DNS server back online, the problem went away and my Linux machines started pulling the full 600 again.

Steps for reproducing this issue:

  1. Have an overengineered network with 2 DNS servers and properly configured DHCP
  2. Turn off primary DNS without altering DHCP settings
  3. Attempt to download games through Linux Steam
  4. Observe speeds.
Kkisak-valve maintainer 2025-04-03 github

Hello @Seqan01, this is most likely a duplicate of #4975 if running a system local dnsmasq (or similar) helps.

SSeqan01 2025-04-03 github

You'll have to forgive me if I am still too new to Linux, but all signs point to being configured to dnsmasq. I am happy to run whatever query and post whatever output to confirm, but you'll have to tell me which.

I did not perform any changes from one to the other prior, during, or after this issue manifesting.

EDIT: I did some reading on the thread, and this may very well be a duplicate. My Primary and Secondary DNS servers are different hosts (Primary is Windows, Secondary is Synology), and Synology may be allergic to the excessive queries referenced in #4975. I'll do some testing.

EDIT the second: Changed my DNS servers and cut the Windows Server completely out of the equation. No change, still pulling at full speed.

Nothing extracted yet.