Hi
Happened me before a year, happened again yesterday after an update which was correlated to pve update. At least the first time it happened I had a pop up message if I would like to update or keep the /etc/network/interfaces file. Now without warning or anything updated, I reboot the server (production environment) and voila. No access to gui / ssh . Afterwards when I logged in from the server itself, I noticed that it had no internet connection even though all the configuration was there and correct.
So with
default via 192.168.77.1 dev vmbr0 onlink linkdown (hmmmm)
192.168.77.0/24 dev vmbr0 proto kernel scope link src 192.168.77.200 linkdown (hmmmm)
with
search your_named_domain.com
nameserver 192.168.77.1 ok here it sees the correct DNS (router or whatever you configured it to look at)
with
noticed that vmbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
This leaded me to check bond0 upon which vmbr0 is based and it was down as well
bond0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
....and the same goes for the two ports the bond0 consists of.
enp25s7: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
enp7s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
That was when I recalled having lived this again in the past. My next stop was interfaces file. So with
I was trying to check each line and see what changed. For one more time it was the same thing.
auto enp7s0
iface enp7s0 inet manual
auto enp0s25
iface enp0s25 inet manual
.....the 2 ports that form the bond0 and bond 0 forms the vmbr0.
It added or uncommented the # I had and couldn t work. After I commented again with # like
#auto enp7s0
iface enp7s0 inet manual
#auto enp0s25
iface enp0s25 inet manual
... saved the file and tried with ifup / ifdown to restart the ports enp7s0 and enp7s0 (interfaces whatever they call them) didn t work. So I tried restarting the bond0 and last the vmbr0 but nothing (with this way).
Anyway, a reboot did the trick of restarting the ports/bonds/vmbrs and voila had net access again and could log in remotely to proxmox and start VMs. There are plenty of reasons of that might happen (ip conflict, router down (oh you didn t check) DNS resolvent ...etc) but I am giving you one more step to check on the process of troubleshooting.
PS I don t know if for some of you works with auto line enabled but for me it doesn t. I guess auto means autostart and not autoconfiguration?
Happened me before a year, happened again yesterday after an update which was correlated to pve update. At least the first time it happened I had a pop up message if I would like to update or keep the /etc/network/interfaces file. Now without warning or anything updated, I reboot the server (production environment) and voila. No access to gui / ssh . Afterwards when I logged in from the server itself, I noticed that it had no internet connection even though all the configuration was there and correct.
So with
ip route
default via 192.168.77.1 dev vmbr0 onlink linkdown (hmmmm)
192.168.77.0/24 dev vmbr0 proto kernel scope link src 192.168.77.200 linkdown (hmmmm)
with
cat /etc/resolv.conf
search your_named_domain.com
nameserver 192.168.77.1 ok here it sees the correct DNS (router or whatever you configured it to look at)
with
ip a
noticed that vmbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
This leaded me to check bond0 upon which vmbr0 is based and it was down as well
bond0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
....and the same goes for the two ports the bond0 consists of.
enp25s7: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
enp7s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
That was when I recalled having lived this again in the past. My next stop was interfaces file. So with
nano /etc/network/interfaces
I was trying to check each line and see what changed. For one more time it was the same thing.
auto enp7s0
iface enp7s0 inet manual
auto enp0s25
iface enp0s25 inet manual
.....the 2 ports that form the bond0 and bond 0 forms the vmbr0.
It added or uncommented the # I had and couldn t work. After I commented again with # like
#auto enp7s0
iface enp7s0 inet manual
#auto enp0s25
iface enp0s25 inet manual
... saved the file and tried with ifup / ifdown to restart the ports enp7s0 and enp7s0 (interfaces whatever they call them) didn t work. So I tried restarting the bond0 and last the vmbr0 but nothing (with this way).
Anyway, a reboot did the trick of restarting the ports/bonds/vmbrs and voila had net access again and could log in remotely to proxmox and start VMs. There are plenty of reasons of that might happen (ip conflict, router down (oh you didn t check) DNS resolvent ...etc) but I am giving you one more step to check on the process of troubleshooting.
PS I don t know if for some of you works with auto line enabled but for me it doesn t. I guess auto means autostart and not autoconfiguration?
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