TerraMaster Forum

My first post here, just bought a T12-500, now running TOS7 v.7.0.1188 with TRAID.

Very different from my old NetGear NAS Pro which was stable for 15 years.
Very powerful and fast, with some great features. And some not so great compared to the 15-year old vintage NAS.

Have a problem I need help with. The Multimedia server is being flaky.
Took me hours to diagnose, and I now know what the problem is. But not the fix.

Situation #1:
LAN #1 = connected to local network. Communication = OK with Win11 PCs
MultiMedia Server works and is discoverable on TVs using VLC Media Player, or any other host of available players for a Sony Android TV
LAN #2 = disconnected

Situation #2:
LAN #1 = connected to local network.
LAN #2 = dedicated to direct connection to PC computer. LAN #2 has different IP address than LAN #1 (of course)
Problem A: MultiMedia Server NOT discoverable on TV.
Tested on multiple TVs attached to the network.
SMB, Upnp both turned ON in the NAS

If I disconnect LAN #2, Media Server becomes immediately visible to all TVs. Problem disappears.
Looks to me like a direct connection to a PC is buggy, but maybe I have some settings set up incorrectly?

Problem B: LAN #2 will not connect to PC, unless I first unplug LAN #1. I can plug in LAN #1 again, AFTER LAN #2 makes the connection with PC. Once the LANs are stabilized, they stay stable.

Are these 2 bugs? I know PCs, but I do not know this NAS.

Any help is much appreciated. Thanks!

Since this is my first post and I am new to the forum, I have no idea if TerraMaster tech staff read these posts, or if there is somewhere else that I should report these problems? Advice on how to best alert T staff to the issue?

In the Multimedia server settings, there is a drop down box to select the enabled lan port. (Hence the presumption is it is only available on one network segment.)
@TM support will be along shortly. There are several staff on this forum but they are in different time zones, so usually they will respond overnight for the west.

Hi Gremlin,
Thanks for the reply. Yes, correct.

My MultiMedia Server is connected on LAN #1, port 8300, ssdp=30. It can only connect to one LAN (local area network)
It *should* have nothing to do with what is happening on LAN #2.
But LAN #2 direct connection to a PC kills the Multimedia Server running on LAN #1.

tnaspain wrote: ↑16 Sep 2026, 01:36

Welcome to the TerraMaster forum!

The symptoms you described are classic indicators of a multicast routing and default gateway conflict introduced when multiple network interfaces are active.

Here is why this happens and how to resolve it:

1. Multicast (SSDP) Redirection: DLNA / Multimedia Server discovery relies on UDP multicast. When LAN #2 connects to the PC, if LAN #2 assigns or receives a default gateway, or if its routing metric takes precedence, Linux may redirect multicast traffic out through LAN #2 instead of LAN #1. As a result, the TVs on LAN #1 never receive the discovery broadcasts.

2. Routing / Gateway Collision: Having a Default Gateway configured on a direct point-to-point connection (LAN #2) confuses the OS routing table, which also explains why LAN #2 struggles to connect until LAN #1 is temporarily disconnected.

Recommended Solutions

1. Remove the Gateway & DNS on LAN #2:

• On both the NAS (LAN #2) and your PC's dedicated network adapter, configure static IPs on a completely different subnet from LAN #1 (e.g., if LAN #1 is 192.168.1.x, set LAN #2 to 10.0.0.x or 192.168.2.x).

• Crucial: Leave the Default Gateway and DNS fields completely empty/blank for LAN #2 on both the NAS and the PC. Only assign the IP address and Subnet Mask (255.255.255.0).

2. Check Default Gateway Priority in TOS:
Go to TOS > Control Panel > Network > Interface, and ensure LAN #1 is designated as the default interface / default gateway.

3. Restart the Multimedia Server:
Once the network settings on LAN #2 are saved without a gateway, disable and re-enable the Multimedia Server app in TOS to re-bind it to the LAN #1 multicast route.

OK, I did some testing, and there are still multiple problems.

Your recommended solution #1 above worked! Or did it?

Problem #1: After doing what you suggested,

But it disconnected LAN#1 again, and only after physically removing and reconnecting LAN #1 multiple times, it stabilized. I checked all cabling with a cable tester, so that is OK. I have 3 LANs on the PC, so tested different ones. Same outcome each time.

Putting LAN #2 a different subnet, the direct connection partially worked and stopped interfering with LAN #1 (once system stabilized), on which I could now see the Multimedia Server directory on the TV, using apps like VLC Media player and few others.

Problem #2: On the NAS, before stabilizing, it throws up an error multiple times saying "URL:/v2/NetworkSet/GetANetworkInterfaces/Message: Network Error "
I have to do ridiculous amounts of unplugging cabling and then trying to reconnect via the TNAS PC desktop app. The app gets confused if it sees more than one LAN. It will NOT log into either LAN if it sees 2 LANs. I have to disconnect one via pulling the cable from the NAS.Then it will finally connect to the NAS.

Problem #3: When LAN #2 (10G) finally connects via the direct connection, it drops LAN #1 (1G, WAN) speed from 1G to 100Mbps. Disconnecting LAN #2 restores LAN #1 speed to 1G.

Problem #4: If the Web interface is closed, I can not open it again.
I can not reach the TNAS from TNAS PC for Windows when both LANS are connected. It gets highly confused. See Problem #2 above.

One happy note:
Solved one big problem: Now, even if I Disable the Multimedia Server app, I can NOW access shared folders on the Android TV directly, without having to go thru the Multimedia Server. Just by logging into each shared folder on the NAS.
Just liek I always wanted to do, without need for some MultiMedia app.

This feature was not available before. Somehow magically shared folders on the NAS appear in VLC Media player on the TV, and they show blank content. Once I log in via the TV into that shared folder, I have access to all the files on that shared folder thru the TV. Problem solved, and I can avoid that Multimedia Server app.

This TNAS should work out of the box. It is highly problematic to set up. I have another big problem with it, but will post that separately. Thanks.