I’am running Ubuntu 18.04.2 LTS failed to install samba

noname@star-death-console:~$ apt-get install samba E: Could not open lock file /var/lib/dpkg/lock-frontend – open (13: Permission denied) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), are you root? noname@star-death-console:~$ su root Password: su: Authentication failure noname@star-death-console:~$ su root Password: root@star-death-console:/home/noname# apt-get install samba Reading package lists… Done Building dependency tree
Reading state information… Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:

The following packages have unmet dependencies: samba : Depends: python (< 2.8) but it is not going to be installed Depends: python-dnspython but it is not going to be installed Depends: python-samba but it is not going to be installed Depends: samba-common-bin (= 2:4.7.6+dfsg~ubuntu-0ubuntu2) but it is not going to be installed Depends: python (>= 2.7~) but it is not going to be installed Depends: python2.7:any Depends: python:any (< 2.8) Depends: python:any (>= 2.7~) Depends: samba-libs (= 2:4.7.6+dfsg~ubuntu-0ubuntu2) but 2:4.7.6+dfsg~ubuntu-0ubuntu2.6 is to be installed Recommends: attr Recommends: samba-dsdb-modules but it is not going to be installed Recommends: samba-vfs-modules but it is not going to be installed E: Unable to correct problems, you have held broken packages. root@star-death-console:/home/noname#

No ethernet after 18.04.2 to 18.04.3 upgrade (LTS)

I upgraded my desktop from Mint 17 to Ubuntu 18.04.2 this past March (KDE desktop).

Today the KDE5 clipboard randomly stopped working (again), so I decided to do all the package upgrades that had piled up and reboot, not realizing 18.04.3 had come out.

I didn’t change any configuration, and now even though every tool confirms my ethernet config is unchanged, the machine is not connected. I was able to connect by booting from the 18.04 live CD, so it’s not a hardware issue.

I wasn’t aware that netplan is a thing, so I tried the answer here which didn’t work.

The corresponding port light on my switch is blinking, but the router doesn’t show this machine in its client list. Restarting the networking and network-manager services accomplishes nothing.

$   ifconfig -a enp5s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500         inet 192.168.1.4  netmask 255.255.255.0  broadcast 192.168.1.255         inet6 fe80::ecb1:ac3e:c98b:504b  prefixlen 64  scopeid 0x20<link>         ether fc:aa:14:21:71:1e  txqueuelen 1000  (Ethernet)         RX packets 0  bytes 0 (0.0 B)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 689  bytes 50531 (50.5 KB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0  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 1695  bytes 145459 (145.4 KB)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 1695  bytes 145459 (145.4 KB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0  
$   lshw -C network   *-network        description: Ethernet interface        product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller        vendor: Realtek Semiconductor Co., Ltd.        physical id: 0        bus info: pci@0000:05:00.0        logical name: enp5s0        version: 06        serial: fc:aa:14:21:71:1e        size: 1Gbit/s        capacity: 1Gbit/s        width: 64 bits        clock: 33MHz        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: autonegotiation=off broadcast=yes driver=r8169 duplex=full firmware=rtl8168e-3_0.0.4 03/27/12 ip=192.168.1.4 latency=0 link=yes multicast=yes port=MII speed=1Gbit/s        resources: irq:16 ioport:b000(size=256) memory:fe600000-fe600fff memory:d0300000-d0303fff 

I noticed these lines in dmesg:

[   27.396723] systemd[1]: network.target: Found ordering cycle on networking-routes.service/start [   27.396726] systemd[1]: network.target: Found dependency on network.target/start [   27.396728] systemd[1]: network.target: Job networking-routes.service/start deleted to break ordering cycle starting with network.target/start 

and

[   51.189046] RTL8211E Gigabit Ethernet r8169-500:00: attached PHY driver [RTL8211E Gigabit Ethernet] (mii_bus:phy_addr=r8169-500:00, irq=IGNORE) [   51.189046] RTL8211E Gigabit Ethernet r8169-500:00: attached PHY driver [RTL8211E Gigabit Ethernet] (mii_bus:phy_addr=r8169-500:00, irq=IGNORE) [   51.406971] r8169 0000:05:00.0 enp5s0: Link is Down [   52.952958] r8169 0000:05:00.0 enp5s0: Link is Up - 100Mbps/Full - flow control rx/tx [   52.952975] IPv6: ADDRCONF(NETDEV_CHANGE): enp5s0: link becomes ready [   53.468053] kauditd_printk_skb: 14 callbacks suppressed 

Why my swap area is set to zero in Ubuntu Server 18.04.2?

By checking the swap size in my Ubuntu server I observed that is set to zero. Since it was installed in very basic configuration from AWS EC2, I’m not sure if I had to do additional steps to adjust swap size area.

I run the following commands and got the below results :

# grep Swap /proc/meminfo    SwapCached:            0 kB    SwapTotal:             0 kB    SwapFree:              0 kB  # swapon -s   #  free -m                  total        used        free      shared  buff/cache   available Mem:           7975         187        7059           0         728        7549 Swap:             0           0           0 

Is it normal to have a swap area set to zero ? If it is not, what should I do to fix it ?

Thanks !

How to make Wavlink USB wifi adapter work in Ubuntu 18.04.2 LTS

Since last kernel update, Wifi adapter stopped working.

Wifi USB adapter: Wavlink AC1300 Dual Band USB Adapter
Model # WL-WN688U8 (Rev.A)

using additional driver

~$   uname -a   Linux PC 5.0.0-23-generic #24~18.04.1-Ubuntu SMP Mon Jul 29 16:12:28 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux 
~$   lsusb Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub (...) Bus 001 Device 007: ID 0bda:8812 Realtek Semiconductor Corp. RTL8812AU 802.11a/b/g/n/ac WLAN Adapter Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub 
~$   lshw -C network WARNING: you should run this program as super-user.   *-network                         description: Ethernet interface        product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller        vendor: Realtek Semiconductor Co., Ltd.        physical id: 0        bus info: pci@0000:03:00.0        logical name: enp3s0        version: 0c        serial: 1c:1b:0d:df:16:70        size: 10Mbit/s        capacity: 1Gbit/s        width: 64 bits        clock: 33MHz        capabilities: bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation        configuration: autonegotiation=on broadcast=yes driver=r8169 duplex=half firmware=rtl8168g-2_0.0.1 02/06/13 latency=0 link=no multicast=yes port=MII speed=10Mbit/s        resources: irq:16 ioport:d000(size=256) memory:f7c00000-f7c00fff memory:f0000000-f0003fff WARNING: output may be incomplete or inaccurate, you should run this program as super-user. 
~$   nmcli device DEVICE  TYPE      STATE        CONNECTION  enp3s0  ethernet  unavailable  --          lo      loopback  unmanaged    -- 

Any help welcome!