@ibit I understand that some ISP offer more than 1Gb; my question was more along the lines of "what other benefits are realized by using the WAN vs. the LAN port for passthrough (as advised by @yuxin.zou near the beginning of this discussion), since it appears to work on both?"
There is no other advantage except the speed.
No other advantage until they release an mmwave capable gl-inet model. Even so, mmwave is not yet deployed on large scale, at least with AT&T.
Is IPv6 working now via passthrough mode? I've not tried this last firmware but I'd always thought it wasn't supported?
@polemarxos Ipv6 passthrough works if you enable IPv6 in router mode first before changing to passthrough mode
1 Like
Didn’t realise that, good to know, thanks!
Passthrough is working as expected in 4.7.4 for me. I noticed the UI is showing Ethernet 1 "Connecting" all the time. I'm currently using the WAN port as the LAN. Still looking to see what is causing the "Connecting" message to show up.
I'm also seeing the same behavior with a Unifi UDM Pro gateway. Basically, the GL-X3000 is not "advertising” the new IP when it's in passthrough mode and the cell network IP changes. So, the gateway needs to force IP renew to get the new IP. Not sure at this point why the reason is.
Edit: I downgraded to 4.4.13, and the issue disappeared. The Unifi UDM Pro gets the bridged cell IP address quickly after it changes.
I realize this thread is about the GL-X3000 (since it includes cellular), but can this same passthrough mode somehow be enabled/work with an MT3000 that has a cellphone tethered to it? @bruce
I did disover an oddity with 4.7.4: with the WAN port to LAN mode, if the cell connection restarts (not IP renewal, although that follows) in passthrough mode, the bridging moves back to eth1 (LAN port).
Also, IPv6 is a bit unstable in that traffic may/may not be passed across the gateway. I wasn't able to get a good sense from the logs as to why this was so. Also, it appears that TMO may be using variable MTU as a means to control bandwidth usage, since it's almost never the same when I test. I had set the MTU on the cell connection based on previous testing to alleviate the 'skb_tailroom small!' log errors, and although this works for a short time, when it reappears, testing shows that cellular MTU has changed again.
Looking forward to the next beta version so I can test it some more.
the eth0 switch to eth1 issue does not occur to me. I'm on AT&T network.
The X3000 was also able to get an ipv6 IP (for AT&T it appears to be a private ipv6) but does not appear to pass it on downstream if the ipv6 mode is set to native.
I also have no problems with switching between eth0 and eth1. I do not get an IPv6 address from my provider. I cannot test this.
@ibit did you enable IPv6 as passthrough in the gateway before you enabled passthrough mode?
Even in router mode, I do not get an IPv6 address from my ISP. It does not bother me. As long as IPv4 works, it is enough for me.
Has anyone figured out how to enable TailScale after passthrough mode? I can start tailscaled and then do tailscale up ... But after rebooting, I have to do this manually AND it doesn't maintain state ... Requiring me to reauthenticate with TailScale, approve routes, etc... any help would be greatly appreciated!
Tailscale should not work. Every connection should be passed through to the router behind it in passthrough mode. If you want to use Tailscale, then your Gl.inet router must be in router mode. If you want to continue using passthrough, the router behind the Gl.inet router must support Tailscale
Hmm - although it shouldn't work, it does 
... Just doesn't survive post reboot. Been tinkering with rc.local to bring it up after boot, but ... no dice. Still have to manually enter commands.
Side note -- When in passthrough mode, I can't seem to access the admin panel on 192.168.8.1 - does a static route need to be configured on my USG or something?
On an unrelated note... I've noticed that even though the GL-X3000 is now in passthrough mode, it's very chatty... It's consuming at least 100mb+ a day even though the USG has never failed over to WAN2 ... Is anyone else experiencing this?
EDIT: Really just talking to the T-Mobile customers ... if your ISP doesn't have CGNAT please ignore!
Folks, what is the advantage you're looking to gain with putting the device in passthrough mode, especially if you're a T-Mobile user? Even in passthrough mode you're behind T-Mobile's carrier grade network address translation (CGNAT) for IPv4 addresses, so you can't expose ports or achieve moderate NAT type for gaming. If you use IPv6 with SLAC and you're hosting v6 services for some purpose such as private cloud (commonly behind Cloudflare) that makes sense, but you can do the same thing with a $4/mo VPS and Cloudflare/Zerotier/Tailscale/custom WireGuard or other VPN provider. I don't see what benefit removing one layer of NAT provides and would rather keep that in place as a buffer between my ISP/neighbors and my actual LAN router. Really curious what use cases you're all looking to satisfy. Thanks!