Proxmox 8 - web UI works for a bit then hangs on connection until reboot

[yatesco]

Hi all. I'm getting a weird issue with connecting to the Proxmox Web UI. Everything works, containers work and are publicly accessible (tailscale), the host works and can ping the world, but eventually (within minutes/hours) the main web UI just stops. Connecting to it just hangs (i.e. it never connects and neither does it immediately fail). When this happens, everything except the web UI is still functioning fine.

Restarting it and the web UI works again.

It is running in Parallels (FWIW) just as I experiment with it. I know this isn't supported, but I don't think this would make a difference...

I don't know where to begin with this, but maybe this helps?:

It is bridged and the bridge has a DHCP IP and `/etc/network/interfaces`:
```
auto lo
iface lo inet loopback

iface enp0s5 inet static

auto vmbr0
iface vmbr0 inet dhcp
bridge-ports enp0s5
bridge-stp off
bridge-fd 0

### the following has a single SDN configured via the UI
source /etc/network/interfaces.d/*
```

`/etc/network/interfaces.d/sdn`:
```
#version:4

auto vmnet
iface vmnet
address 10.12.0.1/24
post-up iptables -t nat -A POSTROUTING -s '10.12.0.0/24' -o vmbr0 -j SNAT --to-source 192.168.1.145
post-down iptables -t nat -D POSTROUTING -s '10.12.0.0/24' -o vmbr0 -j SNAT --to-source 192.168.1.145
post-up iptables -t raw -I PREROUTING -i fwbr+ -j CT --zone 1
post-down iptables -t raw -D PREROUTING -i fwbr+ -j CT --zone 1
bridge_ports none
bridge_stp off
bridge_fd 0
ip-forward on
```

`/etc/hosts`:
```
127.0.0.1 localhost.localdomain localhost
192.168.1.145 Proxmox.localdomain Proxmox

# The following lines are desirable for IPv6 capable hosts

::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
```

`ip a`:
```
root@Proxmox:~# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: enp0s5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmbr0 state UP group default qlen 1000
link/ether 00:1c:42:a8:22:6c brd ff:ff:ff:ff:ff:ff
3: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 00:1c:42:a8:22:6c brd ff:ff:ff:ff:ff:ff
inet 192.168.1.145/24 brd 192.168.1.255 scope global vmbr0
valid_lft forever preferred_lft forever
inet6 fe80::21c:42ff:fea8:226c/64 scope link
valid_lft forever preferred_lft forever
4: vmnet: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 22:8c:23:69:c5:da brd ff:ff:ff:ff:ff:ff
inet 10.12.0.1/24 scope global vmnet
valid_lft forever preferred_lft forever
inet6 fe80::1c08:3dff:fec9:d27/64 scope link
valid_lft forever preferred_lft forever
5: veth900i0@if2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr900i0 state UP group default qlen 1000
link/ether fe:e4:58:d9:25:36 brd ff:ff:ff:ff:ff:ff link-netnsid 0
6: fwbr900i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether f6:bc:b1:3c:c5:2d brd ff:ff:ff:ff:ff:ff
7: fwpr900p0@fwln900i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmnet state UP group default qlen 1000
link/ether 22:8c:23:69:c5:da brd ff:ff:ff:ff:ff:ff
8: fwln900i0@fwpr900p0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr900i0 state UP group default qlen 1000
link/ether f6:bc:b1:3c:c5:2d brd ff:ff:ff:ff:ff:ff
9: veth990i0@if2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr990i0 state UP group default qlen 1000
link/ether fe:bf:e3:d8:f3:26 brd ff:ff:ff:ff:ff:ff link-netnsid 1
10: fwbr990i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 6e:1a:b6:23:ad:47 brd ff:ff:ff:ff:ff:ff
11: fwpr990p0@fwln990i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmnet state UP group default qlen 1000
link/ether 06:02:12:b9:7c:c9 brd ff:ff:ff:ff:ff:ff
12: fwln990i0@fwpr990p0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr990i0 state UP group default qlen 1000
link/ether 6e:1a:b6:23:ad:47 brd ff:ff:ff:ff:ff:ff
```

`ip r`:
```
default via 192.168.1.1 dev vmbr0
10.12.0.0/24 dev vmnet proto kernel scope link src 10.12.0.1
192.168.1.0/24 dev vmbr0 proto kernel scope link src 192.168.1.145
```

As I say, everything works fine - network access from host and containers, but the web UI itself works fine and then just times out.

Any pointers?

Thanks!

 

[bbgeek17]

Have you tried to access the GUI locally from the host via curl, ie:
curl -k https://192.xx.:8006

If that works then the issue is further along the network path.

Good luck

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[yatesco]

Have you tried to access the GUI locally from the host via curl, ie:
curl -k https://192.xx.:8006

If that works then the issue is further along the network path.

Good luck

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

thanks @bbgeek17. I can no longer access the server from ssh or https from outside, but if I log in to the host directly then `curl -k ....:8006` returns the expected page.

 

[bbgeek17]

thanks @bbgeek17. I can no longer access the server from ssh or https from outside, but if I log in to the host directly then `curl -k ....:8006` returns the expected page.

Sounds like it's not just WebUI then?

Your system has a higher complexity than an average install, with a number of technologies at play. My suggestion would be to reduce the number of variables to achieve stable environment. You can add things one at a time to see if anything in particular affects the stability.

Cheers

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[yatesco]

So I removed the SDN and changed to a more "traditional" bridge (static IP on NIC and private bridge with masquerading) and everything is working again and no timeouts so far....

 

[yatesco]

Alas, I spoke to soon. I came back in this morning and no external SSH or HTTPS to the host, but containers are working fine?!

`/etc/network/interfaces` is attached (I can't copy/paste from Parallels - sigh)