Can't access web interface after ISP resetting my router

[kaolas]

I have a Qnap NAS running Proxmox. One day after no internet my ISP reset my router remotely which changed my IP address and after that I couldn't access proxmox through a browser. I logged in SSH without a problem and changed the IP address of proxmox (by using the nano etc/network/interfaces command) but I still couldn't access it with a browser.
I checked the other posts similar to this, but I still can't figure out what's wrong, although I am a noob. I tried different browsers from different devices as well.
I would really appreaciate it if someone could help me. I executed some commands which might help you solve my problem:

ip a
1: 10: <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
valid_lft forever preferred_lft forever
2: enp4s0: <BROADCAST, MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 24:5e:be: 43:7c:12 brd ff:ff:ff:ff:ff:ff
3: enp6s0: <BROADCAST, MULTICAST> mtu 1588 qdisc noop state DOWN group default qlen 1000
link/ether 24:5e:be: 43:7c:11 brd ff ff ff ff ff:ff
4: enp9s0: <NO-CARRIER, BROADCAST, MULTICAST, UP> mtu 1500 qdisc mq master vmbro state DOWN group default qlen 1000
link/ether 24:5e:be: 43:7c:0f brd ff:ff:ff:ff:ff:ff
5: enp11s0: <BROADCAST, MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 24:5e:be: 43:7c:18 brd ff:ff:ff:ff:ff:ff
6: vmbr0: <BROADCAST, MULTICAST, UP, LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 24:5e:be: 43:7c:0f brd ff:ff:ff:ff:ff:ff
inet 192.168.50.36/32 scope global vmbro
valid_lft forever preferred_1ft forever
inet6 fe80::265e: beff: fe43:7c0f/64 scope link
valid_lft forever preferred_1ft forever
7: tap18818: <BROADCAST, MULTICAST, PROMISC, UP. LOWER UP) mtu 1500 qdisc pfifo_fast master fwbr100i0 state UNKNOWN group default qlen 1000
link/ether a2:47:fd:b5:38:4a brd ff:ff:ff:ff:ff:ff
8: fwbr100i0: <BROADCAST, MULTICAST, UP, LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether ba: 62:83:fe:fd:2d brd ff:ff:ff:ff:ff:ff
9: fwpr100p0@fwln100i0: <BROADCAST, MULTICAST, UP, LOWER UP> mtu 1500 qdisc noqueue master vmbre state UP group default qlen 1000
link/ether 96:48:45:c1:80:36 brd ff:ff:ff:ff:ff:ff
10: fwln100i0@fwpr100p0: <BROADCAST, MULTICAST, UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr100i0 state UP group default qlen 1000
link/ether c6:26:35:65:46:f6 brd ff:ff:ff:ff:ff:ff


nmap -p 8006 192.168.50.36
Starting Nmap 7.93 ( https://nmap.org ) at 2024-03-16 09:21 CET
Nmap scan report for yumyum (192.168.50.36)
Host is up (0.00016s latency).
PORT STATE SERVICE
8006/tcp open wpl-analytics
Nmap done: 1 IP address (1 host up) scanned in 0.14 seconds


systemctl status pveproxy.service
pveproxy.service PVE API Proxy Server
Loaded: loaded (/lib/systemd/system/pveproxy.service; enabled; preset: enabled)
Active: active (running) since Sat 2024-03-16 10:03:06 CET; 5min ago
Process: 1043 ExecStartPre=/usr/bin/pvecm updatecerts --silent (code=exited, status=8/SUCCESS)
Process: 1045 ExecStart=/usr/bin/pveproxy start (code=exited, status=0/SUCCESS)
Main PID: 1047 (pveproxy)
Tasks: 4 (limit: 9390)
Memory: 141.4M
CPU: 1.998s
CGroup: /system.slice/pveproxy.service
-1047 pveproxy
-1048 "pveproxy worker"
-1849 "pveproxy worker"
-1050 "pveproxy worker"

Mar 16 10:03:05 yumyum systemd[1]: Starting pveproxy.service PVE API Proxy Server...
Mar 16 10:03:06 yumyum pveproxy [1047]: starting server
Mar 16 10:03:06 yumyum pveproxy [1047]: starting 3 worker(s)
Mar 16 10:03:06 yumyum pveproxy [1047]: worker 1048 started
Mar 16 10:03:06 yumyum pveproxy [1047]: worker 1049 started
Mar 16 10:03:06 yumyum pveproxy [1047]: worker 1050 started
Mar 16 10:03:06 yumyum systemd[1]: Started pveproxy.service PVE API Proxy Server.

 

[leesteken]

6: vmbr0: <BROADCAST, MULTICAST, UP, LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 24:5e:be: 43:7c:0f brd ff:ff:ff:ff:ff:ff
inet 192.168.50.36/32 scope global vmbro

Should this not be 192.168.50.36/24 or /16? What is the subnet (and/or DHCP-range) of the router? Did you change /etc/network/interfaces (because /32 would probably not have worked before)?

 

[kaolas]

I tried with both (/24 and /16), but it still doesn't work.

Router address: 192.168.50.1
Subnet mask: 255.255.255.0

DHCP
IP Pool Starting Address: 192.168.50.2
IP Pool Ending Address: 192.168.50.254

I changed it because router address changed from 192.168.0.1. I might have only needed to change the gateway thinking about it retrospectively.

 

[leesteken]

Router address: 192.168.50.1
Subnet mask: 255.255.255.0

Then use /24 instead of /32

DHCP
IP Pool Starting Address: 192.168.50.2
IP Pool Ending Address: 192.168.50.254

The IP address 192.168.50.36/24 is inside the DHCP-range and Proxmox does not use DHCP. Better to shrink the DHCP-range on the router and select an IP address outside of it.

I tried with both (/24 and /16), but it still doesn't work.

/24 should just work (after a reboot). Maybe something else was not right (like the gateway) or it's because of the overlap with DHCP. Show the whole /etc/network/interfaces if the above does not work.

 

[kaolas]

Then use /24 instead of /32

The IP address 192.168.50.36/24 is inside the DHCP-range and Proxmox does not use DHCP. Better to shrink the DHCP-range on the router and select an IP address outside of it.

/24 should just work (after a reboot). Maybe something else was not right (like the gateway) or it's because of the overlap with DHCP. Show the whole /etc/network/interfaces if the above does not work.

I rewrote it to /24 and rebooted it but it still doesn't work for some reason.

nano /etc/network/interfaces
i face enp9s0 inet manual
auto vmbr0
iface vmbr0 inet static
address 192.168.50.36/24
gateway 192.168.50.1
bridge-ports enp9s0
bridge-stp off
bridge-fd 0
iface enp4s0 inet manual
iface enp6s0 inet manual
iface enp11s0 inet manual

 

[leesteken]

I rewrote it to /24 and rebooted it but it still doesn't work for some reason.

bridge-ports enp9s0

4: enp9s0: <NO-CARRIER, BROADCAST, MULTICAST, UP> mtu 1500 qdisc mq master vmbro state DOWN group default qlen 1000

Looks like there is no (working) cable connected between the physical port of enp9s0 and your router.

 

[kaolas]

What I may have mentioned before is that I have a modem in bridge mode which connects to a router and that is connected with a secondar router with an ethernet cable. I connected my NAS to the secondary router and it worked fine as I said before my ISP reset the modem.
So now I connected the NAS to the primary router with an ethernet cable, however it still says with the ip a command in the enp9s0 line that there is no carrier.
I'm 100% sure the cable is fine (it works with my laptop and PC). Does that mean that the NAS' ethernet port gone bad?

 

[leesteken]

So now I connected the NAS to the primary router with an ethernet cable, however it still says with the ip a command in the enp9s0 line that there is no carrier.
I'm 100% sure the cable is fine (it works with my laptop and PC). Does that mean that the NAS' ethernet port gone bad?

I don't know but there if there is no carrier then there is no working connected. Maybe it cannot negotiate a speed/duplex or one of the sides is bad. Check the cable, try different devices on both ends, etc. Maybe try to use and configure a different network device/port for Proxmox. This is not Proxmox specific, so other Linux guides and hardware troubleshooting guides can apply.

 

[kaolas]

Thank you very much, I'll try those thing and post back with the results.

 

[kaolas]

Oh my god, the cable was in the wrong ethernet port (my NAS has 4) and I didn't notice that, it works now. So dumb. Anyway, thank you very much for your help!