Since this morning the network is unreachable Ubuntu 18:04

debugcn Published at Dev

user2315094

This morning the networking in my Ubuntu 18.04 Server Edition is not working anymore :

marco@pc01:$ sudo lshw -class network
  *-network DISABLED
      description: Ethernet interface
      product: RTL8111/8168/8411 PCI Express 
        Gigabit Ethernet Controller
  *-network DISABLED
      description: Wireles interface
      product: AR9227 Wireless Network Adapter
  *-network:0
       description: Ethernet interface
       physical id: 2
       logical name : docker0
  *-network:1
       description: Ethernet interface
       physical id: 3

sudo nano /etc/nework/interfaces :

iface eth0 inet static
    address 192.168.1.7
    netmask 255.255.255.0
    network 192.168.1.1 
    broadcast 192.168.0.255
    post-up iptables-restore <  
      /etc/iptables.up.rules
    gateway 192.168.1.1
    dns-nameservers 192.168.0.5 8.8.8.8

marco@pc01:$ sudo service network-manager restart
 Failed to restart network-manager.service: Unit network-manager.service 
  not found

Even with sudo /etc/init.d/networking restart:

marco@pc01:$ sudo /etc/init.d/networking restart
[ok] Restarting networking (via systemctl):
 networking.service

marco@pc01:$ ping 192.168.1.4
 connect: Network is unreachable

What have I to do in order to make the network available again? Looking forward to your kind help Marco

1° Update:

marco@pc01:$ ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKOWN group
       default qlen 1000
   inet 27.0.0.1/8 scope host lo
     valid_lft forever preferred_lft forever
   inet6 ::1/128 scope host
     valid_lft forever preferred_lft forever
2: enp3s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group 
       default qlen 1000
     link/ether 78:24:af:43:ef:5c brd ff:ff:ff:ff:ff:ff
3: wlp5s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group 
       default qlen 1000
     link/ether c0:4a:00:09:0e:80 brd ff:ff:ff:ff:ff:ff  
4: b3-4f9fe03b1a66: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc 
       noqueue state DOWN group default
     link/ether 02:42:64:29:65:73 brd ff:ff:ff:ff:ff:ff
     inet 172.22.0.1/16 brd 172.22.255.255 scope global br-4f9fe03b1a66
       valid_lft forever preferred_lft forever
5: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue 
      state DOWN group default
    link/Ether 02:42:01:ea:90:66 brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.1/16 brd 172.17.255.255 scoper global docker0
      valid_lft forever preferred_lft forever

2°Udate:

marco@pc01:$ ifconfig eth0 up eth0: ERROR while getting interface flags: 
  eth0: ERROR while getting interface flgs: No such device
  eth0: Host name lookup failure

marco@pc01:$ ifconfig
br-4f9feo3b1a66: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
    inet 192.22.0.1 netmask 255.255.0.0 broadcast 172.22.255.255
    ether 02:42:4d:c4:bd:62 txqueuelen 0 (Ethernet) 
    RX packets 0 bytes 0 (0.0B)
    RX errors 0 dropped 0 overruns 0 frame 0
    TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

docker0: flags=4099<,UP,BROADCAST,MULTICAST> mtue 1500
    inet 172.17.0.1 netmask 255.255.0.0 broadcast 172.17.255.255
    ether 02:42:24:b9:3b:59 txqueuelen 0 (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

l0: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
    inet 127.0.0.1 netmask 255.0.0.0
    inet6 ::1 prefoxlen 128 scopeid 0x10<host>
    loop txqueuelen 1000 (Local Loopback)
    RX packets 258 bytes 32343 (32.3 KB) 
    RX errors 0 dropped 0 overruns 0 frame 0
    TX packets 258 bytes 32343 (32.3 KB)  
    TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

/etc/network/interfaces :

  auto lo
  iface lo inet loopback

3° Update:

I modified the /etc/network/interfaces file as follows:

iface enp3s0 inet static
    address 192.168.1.7
    netmask 255.255.255.0
    network 192.168.1.1 
    broadcast 192.168.0.255
    post-up iptables-restore <  
      /etc/iptables.up.rules
    gateway 192.168.1.1
    dns-nameservers 192.168.0.5 8.8.8.8

But still no network.

4° Update:

  marco@pc01:$ uname -r
  4.15.0-55-generic

  marco@pc01:$ ls -al /etc/netplan
  total 20
  drwxr-xr-x 2 root root 4096 Jul 25 18:37
  drwxr-xr-x 128 root root 12288 Jul 25 12:51
  -rw-r--r-- 1 root root 616 Jul 25 18:37 30-cloun-init.yaml

   etc/netplan/50-cloud-init.yaml    :

     network:
         renderer: NetworkManager/ networkd
         ethernets:
           enp3s0:
               addresses: [192.168.1.7/24]
               gateway4: 192.168.1.1
               nameservers:
                   addresses: [8.8.8.8,8.8.4.4]
               dhcp4: no
         version: 2

 marco@pc01:$ sudo netplan apply
 sudo: netplan: command not found

For sudo llshw -c network : see above

5° Update : result of dpkg -l netplan

marco@pc01:$ dpkg -l *netplan*
Desired=Unknown/Install/Remove/Purge/Hold
  Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-
       pend
    Err?=(none)/Reinst-required (Status,Err: uppercase=bad)

    Name              Version       Architecture  Description
    in netplan.io      <none>          amd64      (no description 
                                                   available)

6° Update : sudo lshw -c network

marco@pc01:$ sudo lshw -c network
  *-network DISABLED
      description : Ethernet interface
      product: RTL811178168/8411 PCI Express Gigabit Ethernet Controller
      vendor: Realtek Semiconductor CO., Ltd.
      physical id: 0
      bus info: pci@000:03:00.0
      logical name: enp3s0
      version: 11
      serial: 78:24:af:43:ef:5c
      size: 100 Mbit/s
      capacity: 1Gbit/s
      width: 64 bits
      clock: 33 Mhz
      capabilities: pm msi pciexpress msix vpd bus_master cap_list 
                    ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 
                    1000bt 1000bt-fd autonegotiation
      configuration: autonegotiaion=on broadcast=yes driver=r8169 
                     driverversion=2.3LK-NAPI duplex=full latency=0 
                     link=no multcast=yes port=MII speed=100Mbit/s 
      resources: irq:18 ioport:d000(size=256) memory:f7200000-f7200fff 
                 memory:f2100000-f2103fff
   *-network DISABLED
      description: Wireless interface
      product: AR9227 Wireless NEtwork Adapter
      vendor: Qualcomm Atheros
      physical id: 0
      bus info: pci@0000:05:00.0
      logical name: wlp5s0
      version: 01
      serial: c0:4a:00:09:0e:80
      width: 32 bits
      clock: 66MHz
      capabilities: pm bus_master cap_list ethernet physical wireless
      configuration: broadcast=yes driver=ath9k driverversion=3.15.0-55-
                     generic firmware=N/A latency=168 link=no 
                     multicast=yes wireless=IEEE 802.11
      resources: irq:19 memory:f7100000-f10ffff
   *-network:0
      description: Ethernet interface
      physical id: 2
      logical name: docker0
      serial: 02:42:62:12:98:6e
      capabilities: ethernet physical
      configuration: broadcast=yes driver=bridge driverversion=2.3 
                     firmware=N/A ip=172.17.0.1 link=no multicast=yes
   *-network:1
       description: Ethernet interface
       physical id:3
       logical name: br-4f9fe03b1a66
       serial: 01:42:fc:9e:92:1c
       capabilities: ethernet physical
       consiguration: broadcast=yes driver=bridge driverversion=2.3 
                      firmware=N/A ip=172.22.0.1 link=no multicast=yes

7° update:

Two disks: 
  1° disk: 
    /dev/sda1 1M BIOS boot 
    /dev/sda2 1G Linux filesystem /dev/sda3 232G Linux filesystem 
     with sudo fsck -f : everything ok ;
  2° disk: 
    /dev/sdb1 1M BIOS boot 
    /dev/sdb2 232G Linux filesystem

    sudo fsck -f /dev/sdb1
    fsck from util-linux 2.31.1
    e2fsck 1.44.1 (24-Mar-2018)
    ext2fs_open2: Bad magic number in super-block
    fsck.ext2: Supeblock invalid, trying backup blocks...
    fsck.ext2: Bad magic number in super-block whule trying to open 
               /dev/sdb1
      The superblock could not be read or does not describe a valid 
ext2/ext3/ext4 filesystem (and not swap or ufs or something else), then 
the superblock is corrupt, and you might try running e2fsck with an
alternate superblock:
  e2fsck -b 8193 <device>
or
  e2fsck -b 32768 <device>

Can I install netplan even if /dev/sdb1 might contain a corrupted superblock?

8°update:

ubuntu@ubuntu:$ sudo fsck -f /dev/sda2
fsck fromutil-linux 2.31.1
e2fsck 1.44.1 (24-Mar-2018)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/sda2: 309/65536 files (2.9% non-contiguous), 48744/262144 blocks

ubuntu@ubuntu:$ sudo fsck -f /dev/sdb2
fsck from util-linux 2.31.1

9° update: After modifying /etc/netplan/01-network-manager-all.yaml :

ubuntu@ubuntu:/etc/netplan$ sudo netplan --debug generate
DEBUG:command generate: running ['/lib/netplan/generate']
** (generate:4715): DEBUG: 15:57:43.284: Processing input file 
                    /etc/netplan/01-network-manager-all.yaml..
** (generate:4715): DEBUG: 15:57:43.285: starting new processing pass
                    to 1
** (generate:4715): DEBUG: 15:57:43.285: Configuration is valid
** (generate:4715): DEBUG: 15:57:43.285: Generating output files..
** (generate:4715): DEBUG: 15:57:43.285: NetworkManager: definition 
                    enp3s0 is not for us (backend 1)

heynnema

Your /etc/network/interfaces file should be:

auto lo
iface lo inet loopback

Your /etc/netplan/*.yaml file should be:

network:
  version: 2
  renderer: networkd
  ethernets:
    enp3s0:
      addresses: [192.168.1.7/24]
      gateway4: 192.168.1.1
      nameservers:
        addresses: [8.8.8.8,8.8.4.4]

and then you should execute:

sudo netplan generate # generate config files

sudo netplan apply # apply config

reboot # reboot computer

Update #1:

Something is really strange with your computer...

the sudo lshw -C network command isn't giving a complete answer
unless it's a manual typo(s), the /etc/netplan directory and file contents are weird
netplan doesn't seem to be installed

You'd better check your file system before we reinstall netplan...

boot to a Ubuntu Live DVD/USB
open a terminal window by pressing Ctrl+Alt+T
type sudo fdisk -l
identify the /dev/sdXX device name for your "Linux Filesystem"
type sudo fsck -f /dev/sdXX, replacing sdXX with the number you found earlier
repeat the fsck command if there were errors
type reboot