4G modem and Proxmox: Interface doesn't come back up after crash

[Deleted member 91648]

Hello everyone!

As my internet connection is pretty bad, I've bought a 4G router I use to get decent internet speed (Aircard 785S). This router is connected to Proxmox via USB and is detected both as a USB device and a network device (Under the name `enx...`).

I use a pfSense VM in Proxmox to offer this connection to my LAN.

First, I tried sharing my Aircard to pfSense through a USB Device in Proxmox. However, the Aircard seems to sometimes (Around one time per day) reset the USB connection for half a second. Whenever this happened, my pfSense which doesn't support interface hotplug simply crashed.

I asked Reddit for help (https://www.reddit.com/r/PFSENSE/comments/fwhrnf/pfsense_crashes_on_interface_change/) and was advised to share the Aircard through a network bridge instead of a USB device, which makes a lot of sense.

I created a Linux Bridge in Proxmox, linked to `enx...` and added it to my VM. This works perfectly and fixed the crashes in my VM whenever the Aircard reset itself.

However, when the USB connection is reset, the Proxmox interface (`enx...`) goes from `Active: yes` to `Active: no` and never goes back to `Active: yes` despite the router being available shortly after. This makes pfSense unable to renew the IP using DHCP or communicate with the Aircard once this happened and I loose my internet access.

The only working way I found to fix this issue is to reboot the Proxmox host, which is a pain as I have to shutdown all my VMs.

I've tried SSH'ing into my Proxmox host and running `ip link set enx... up`: the interface does show up as `Active: yes` in Proxmox but still doesn't work, even after rebooting the VM. I also tried to restart the Linux bridge linked to the interface without success.

I'm looking for any way that would allow me not to have to reboot my host every day.

Thank you for any help you might provide.

 

[oguz]

hi,

maybe the root of the problem is the easiest to solve. (instead of trying to workaround)

However, the Aircard seems to sometimes (Around one time per day) reset the USB connection for half a second.

what do you see in the logs/journals when this happens?

is this somehow a feature that you can disable on the router maybe?

 

[Deleted member 91648]

Hello,

Thanks a lot for taking the time to answer me. Unfortunately, before looking for a workaround, I tried all the settings I could on the Aircard without any success.

As far as I know, it doesn't have any logging capabilities so I tweaked with the settings that I thought might have some negative effects (Disabled wifi to only let USB tethering, remove the SIM pin as it was frequently asked to enter it again, disabled screen, simplified the router config, etc.).

This is why I'm looking for a way for Proxmox to handle this issue.

Note: Since there is no logs on the Aircard side, I looked at dmesgon Proxmox side. Here is a look at the relevant part:

[  647.234932] fwbr104i0: port 2(tap104i0) entered blocking state

[  647.234933] fwbr104i0: port 2(tap104i0) entered forwarding state

[  647.327037] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0

[  647.327053] ftdi_sio 2-1.2.4:1.0: device disconnected

[  648.161001] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  648.941011] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  649.452994] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  654.672984] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  655.085002] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  656.320994] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  657.192987] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  657.873010] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  658.416988] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[  658.940978] usb 2-1.2.4: reset full-speed USB device number 4 using ehci-pci

[ 5709.083312] perf: interrupt took too long (2530 > 2500), lowering kernel.perf_event_max_sample_rate to 79000

[ 9403.618716] perf: interrupt took too long (3186 > 3162), lowering kernel.perf_event_max_sample_rate to 62750

[14108.392370] perf: interrupt took too long (4000 > 3982), lowering kernel.perf_event_max_sample_rate to 50000

[20003.240057] perf: interrupt took too long (5007 > 5000), lowering kernel.perf_event_max_sample_rate to 39750

[31128.365426] perf: interrupt took too long (6269 > 6258), lowering kernel.perf_event_max_sample_rate to 31750

[51762.438964] perf: interrupt took too long (7840 > 7836), lowering kernel.perf_event_max_sample_rate to 25500

[95002.808204] usb 1-1.5: USB disconnect, device number 5

[95002.809989] rndis_host 1-1.5:1.0 enx00a0c6000000: unregister 'rndis_host' usb-0000:00:1a.0-1.5, RNDIS device

[95002.810790] vmbr3: port 1(enx00a0c6000000) entered disabled state

[95002.811424] device enx00a0c6000000 left promiscuous mode

[95002.811429] vmbr3: port 1(enx00a0c6000000) entered disabled state

[95013.793957] usb 1-1.5: new high-speed USB device number 8 using ehci-pci

[95013.930090] usb 1-1.5: New USB device found, idVendor=0846, idProduct=68e1, bcdDevice= 2.28

[95013.930095] usb 1-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3

[95013.930098] usb 1-1.5: Product: AirCard 785S-100

[95013.930101] usb 1-1.5: Manufacturer: NETGEAR, Inc.

[95013.930103] usb 1-1.5: SerialNumber: 353544061123071

[95013.944502] rndis_host 1-1.5:1.0 eth0: register 'rndis_host' at usb-0000:00:1a.0-1.5, RNDIS device, 00:a0:c6:00:00:00

[95013.953627] rndis_host 1-1.5:1.0 enx00a0c6000000: renamed from eth0

[95016.632333] usb 1-1.5: USB disconnect, device number 8

[95016.632404] rndis_host 1-1.5:1.0 enx00a0c6000000: unregister 'rndis_host' usb-0000:00:1a.0-1.5, RNDIS device

[95027.609977] usb 1-1.5: new high-speed USB device number 9 using ehci-pci

[95027.738124] usb 1-1.5: New USB device found, idVendor=0846, idProduct=68e1, bcdDevice= 2.28

[95027.738128] usb 1-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3

[95027.738130] usb 1-1.5: Product: AirCard 785S-100

[95027.738131] usb 1-1.5: Manufacturer: NETGEAR, Inc.

[95027.738132] usb 1-1.5: SerialNumber: 353544061123071

[95027.752365] rndis_host 1-1.5:1.0 eth0: register 'rndis_host' at usb-0000:00:1a.0-1.5, RNDIS device, 00:a0:c6:00:00:00

[95027.756807] rndis_host 1-1.5:1.0 enx00a0c6000000: renamed from eth0

[154864.716363] device tap200i0 entered promiscuous mode

[154864.746865] fwbr200i0: port 1(fwln200i0) entered blocking state

[154864.746869] fwbr200i0: port 1(fwln200i0) entered disabled state

[154864.746997] device fwln200i0 entered promiscuous mode

[154864.747065] fwbr200i0: port 1(fwln200i0) entered blocking state

[154864.747067] fwbr200i0: port 1(fwln200i0) entered forwarding state

[154864.751161] vmbr0: port 6(fwpr200p0) entered blocking state

[154864.751163] vmbr0: port 6(fwpr200p0) entered disabled state

[154864.751236] device fwpr200p0 entered promiscuous mode

[154864.751270] vmbr0: port 6(fwpr200p0) entered blocking state

[154864.751271] vmbr0: port 6(fwpr200p0) entered forwarding state

[154864.755353] fwbr200i0: port 2(tap200i0) entered blocking state

[154864.755355] fwbr200i0: port 2(tap200i0) entered disabled state

[154864.755476] fwbr200i0: port 2(tap200i0) entered blocking state

[154864.755478] fwbr200i0: port 2(tap200i0) entered forwarding state

[154875.934484] device tap201i0 entered promiscuous mode

[154876.002184] fwbr201i0: port 1(fwln201i0) entered blocking state

[154876.002187] fwbr201i0: port 1(fwln201i0) entered disabled state