Hi all,

 

I’ve been dealing with a frustrating network issue on my Unraid server (version 6.12.13) for several months, and after diving deeper into troubleshooting today, I’m still unable to resolve it. Despite my experience with Unraid and Linux, I’m coming up short, so I’m hoping someone in the community can help shed light on this.

 

TL;DR:

 

• I have gigabit speeds from my ISP (Cox Communications).

• Running speed tests directly in the Unraid terminal results in speeds between 600-750 Mbps, which is expected.

• However, all Docker containers are limited to around 100 Mbps download speeds, regardless of configuration.

 

Full Details:

 

This issue became apparent a few months ago when I noticed one of my Docker applications was stuck downloading at around 100 Mbps. To investigate, I installed a Speedtest Docker container, and it also reported speeds of 96 Mbps down and 98 Mbps up, confirming the cap. Testing further, I plugged the same Ethernet cable into my laptop, and speeds jumped up to 800 Mbps, so I knew the issue was with Docker on Unraid.

 

Steps I’ve Taken to Troubleshoot:

 

1. Speedtest on Host: Running speedtest-cli directly on the Unraid server consistently shows 500-750 Mbps, proving the host system is receiving the correct speeds from my ISP.

2. Network Mode Changes: I tried switching the Docker containers from bridge mode to host mode in an attempt to bypass any internal Docker network limitations, but this didn’t help.

3. Swapped Between ipvlan and macvlan: Given that Unraid made ipvlan the default in recent years, I tried switching between the two network drivers. Unfortunately, this didn’t resolve the issue either.

4. Rewrote daemon.json: I followed recommendations from ChatGPT to rewrite my Docker daemon.json file for optimization, but again, no improvement.

5. Multiple Docker Containers Tested: I ran speed tests across several different Docker containers, but they all max out at around 100 Mbps download—even though I know the server itself can handle much higher speeds.

 

Network Information:

 

• Bonding: Disabled bonding since I only have one NIC (onboard).

• Bridging: Enabled bridging.

• MTU: Set to 1500 (default for standard Ethernet).

• NIC: I’m using the onboard Ethernet from my motherboard, which is an Intel I211 Gigabit Network Connection.

• Driver: igb (version 6.1.106-Unraid).

• Speed: 1 Gbps (full duplex), confirmed via ethtool eth0.

 

Here’s the full output of ethtool eth0:

🌶 :/etc/docker$ ethtool eth0
Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Auto-negotiation: on
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
MDI-X: off (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes

 

The Unraid terminal speed test shows speeds between 500-750 Mbps, while Docker containers consistently max out at 100 Mbps.

 

Other Considerations:

 

• Cabling: I terminate my own Ethernet cables and have tested them. My hardware is capable of steady 1 Gbps speeds, as proven by tests outside Docker.

• CPU/Memory: Server load is minimal, with CPU usage below 10% and memory at around 20%.

• No Bonding: I’ve disabled bonding as I only have one NIC, and I’m using ipvlan as the network driver.

 

At this point, I’m out of ideas. The server itself is consistently getting gigabit speeds, but Docker containers are stuck around 100 Mbps. This seems to be an issue that others have encountered, but I haven’t found a solution. For reference, here’s a related thread I found on Reddit: Docker Speeds Limited to 100Mbps.

 

Any help or suggestions would be greatly appreciated! My neighborhood is getting 5Gbps symmetrical and I want to upgrade to at least 2.5G but if I'm stuck at 100Mbps on my containers. Well, that sucks.

 

Thanks in advance!

I find myself with a very similar issue but the difference is that even on unraid as console I get the same under 100Mbit speeds, so the issue is not really docker.

 

I have a Qnap box with 3 interfaces (2x2.5 and 1x10GB) which are configured in bridge mode (br0) but only the first interface is connected and is connected at 1000 Mbits speed as due to my internal switch limitations.

 

`ethtool eth0 | grep Speed` reports 1000Mbit but a simple test with reports ~75 Mbit/s speeds. Same test run from my macbook while connected on wifi reports, ~300Mbit/s which is much closer to the advertised fiber speed. 

 

I am starting to believe that unraid might have problems with the network drivers. Note the one connected is the intel one:

 

```

sudo lspci | grep -Ei 'eth|network|ethernet|wireless|wifi'
05:00.0 Ethernet controller: Aquantia Corp. AQtion AQC107 NBase-T/IEEE 802.3an Ethernet Controller [Atlantic 10G] (rev 02)
06:00.0 Ethernet controller: Intel Corporation Ethernet Controller I225-V (rev 03)
07:00.0 Ethernet controller: Intel Corporation Ethernet Controller I225-V (rev 03)

```

 

Maybe someone can provide some hints here... Ahh, forgot, I am using the latest 7.0rc unraid.

Edited January 5, 20251 yr by ssbarnea