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Ubuntu 18.04.4 LTS production server: no network, no ip adress & No carrier

ca flag

We have a dedicated offsite server in a server center and yesterday suddenly we lost connection to the production server. No one was working on the server at the time. I only have a RemoteConsole access to the server.

When i ping something it states

ping 8.8.8.8
connect: Network is unreachable

The Ubuntu 18.04 server looks like it has lost connection to the public network. Customer service at the server center is closed till Monday. I tried everything I could find about this issue only the main difference with all examples i could find is the the "link detected: no"

$ ethtool eth0
Settings for eth0:
    Supported ports: [ TP ]
    Supported link modes:   10baseT/Half 10baseT/Full 
                            100baseT/Half 100baseT/Full 
                            1000baseT/Full 
    Supported pause frame use: Symmetric
    Supports auto-negotiation: Yes
    Supported FEC modes: Not reported
    Advertised link modes:  10baseT/Half 10baseT/Full 
                            100baseT/Half 100baseT/Full 
                            1000baseT/Full 
    Advertised pause frame use: Symmetric
    Advertised auto-negotiation: Yes
    Advertised FEC modes: Not reported
    Speed: Unknown!
    Duplex: Unknown! (255)
    Port: Twisted Pair
    PHYAD: 1
    Transceiver: internal
    Auto-negotiation: on
    MDI-X: off (auto)
    Supports Wake-on: pumbg
    Wake-on: g
    Current message level: 0x00000007 (7)
                   drv probe link
    Link detected: no

Link detection is none & there is no carrier in the ip link

$ ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
    link/ether ac:1f:6b:9a:6f:a8 brd ff:ff:ff:ff:ff:ff
3: eth1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
    link/ether ac:1f:6b:9a:6f:a9 brd ff:ff:ff:ff:ff:ff

$ ifconfig -a
eth0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether ac:1f:6b:9a:6f:a8  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device memory 0xdf200000-df27ffff  

eth1: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether ac:1f:6b:9a:6f:a9  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device memory 0xdf100000-df17ffff  

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 121044  bytes 20083796 (20.0 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 121044  bytes 20083796 (20.0 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ip4 adres is not showing

$ dhclient

Is just not responding with anything, just a blank spot blinking

Is it really a cable issue at the server center or can i try some more things? And is it possible to scp or rsync data out of the server without network? I tried but errors

rsync: connection unexpectedly closed (0 bytes received so far) [receiver]
rsync error: unexplained error (code 255) 

We backup the server on the same server.....

Help is much appreciated

David avatar
cn flag
Since there is no Ubuntu version 18 what version are you running? We backup the server on the same server..... a joke correct?
SteinB avatar
ca flag
@David Sorry, we run Ubuntu 18.04.4 LTS. Im a fronted dev and server managent isnt my main job. We are learning from this the hard way...
SteinB avatar
ca flag
I rebooted it multiple times. Server logs didn't show any weird things or warnings. Checked it. Also tried booting in recovery mode but it keeps hanging on "Loading initial ramdisk" Left it for 20 min before hard reboot...
guiverc avatar
cn flag
Ubuntu 18.04.4 also implies it's a more than a year behind on security fixes & upgraded packages (https://fridge.ubuntu.com/2020/08/14/ubuntu-18-04-5-lts-released/ shows the ISO release for 18.04.5; but a fully upgraded 18.04 system will report itself as 18.04.6 currently). Is it kept updated? or have you implemented changes that have prevented you from applying updates a year+ ago? and you've been trying to fix the issues only just discovered? causing this issue.. if so giving details of what you've done may help
user535733 avatar
cn flag
If you have access to GRUB during boot, try an older kernel. Does an older kernel that used to boot properly now hang the same way ("*Loading initial ramdisk*")?
SteinB avatar
ca flag
@guiverc I'm trying night and day to getting network connection back since we lost connection yesterday. Read every post about this on askubuntu and tried so many things to get it back. We have 2 more servers at this serverpark and the settings are the same everywhere. I tried many things and if they didn't work I reverted to the original state. I cant update the system cause i can't download the packages with no connection.
SteinB avatar
ca flag
@user535733 When I was in the bootmenu the only options I had was the normal kernel or the recovery option. Sadly no other options where available

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