How to make my Bluetooth keyboard work with Ubuntu 18.04?

I just bought a new Bluetooth Keyboard, and it won’t work with Ubuntu 18.04. Most of the time, pairing fails. On the rare occasions it worked, they keypress were laggy (delay after the press, or one keypress produces multiple characters) until the connection just dropped.

What I did:

  • Paired the keyboard with my smartphone: it works
  • Paired an Apple Bluetooth keyboard with my ubuntu: it works

I’m not familiar at all with bluetooth troubleshooting.

Using bluetoothctl, I tried to manually trust, pair and connect to the keyboard. Pair fails:

pair 76:11:02:01:00:C0 Attempting to pair with 76:11:02:01:00:C0 Failed to pair: org.bluez.Error.Failed 

Here’s the bluetooth service status:

XPS:~$   systemctl status bluetooth.service ● bluetooth.service - Bluetooth service    Loaded: loaded (/lib/systemd/system/bluetooth.service; enabled; vendor preset: enabled)    Active: active (running) since Sat 2019-04-20 11:24:42 CEST; 5h 53min ago      Docs: man:bluetoothd(8)  Main PID: 1053 (bluetoothd)    Status: "Running"     Tasks: 1 (limit: 4915)    CGroup: /system.slice/bluetooth.service            └─1053 /usr/lib/bluetooth/bluetoothd  avril 20 13:06:10 Eric-XPS bluetoothd[1053]: connect error: Host is down (112) avril 20 13:06:29 Eric-XPS bluetoothd[1053]: Can't get HIDP connection info avril 20 13:06:35 Eric-XPS bluetoothd[1053]: connect error: Host is down (112) avril 20 13:06:51 Eric-XPS bluetoothd[1053]: Can't get HIDP connection info avril 20 13:06:57 Eric-XPS bluetoothd[1053]: connect error: Host is down (112) avril 20 13:07:09 Eric-XPS bluetoothd[1053]: Can't get HIDP connection info avril 20 13:07:14 Eric-XPS bluetoothd[1053]: connect error: Host is down (112) avril 20 17:03:23 Eric-XPS bluetoothd[1053]: 76:11:02:01:00:C0: error updating services: Input/output error (5) avril 20 17:05:01 Eric-XPS bluetoothd[1053]: Refusing input device connect: No such file or directory (2) avril 20 17:05:01 Eric-XPS bluetoothd[1053]: Refusing connection from 76:11:02:01:00:C0: unknown device 

And here’s the hardware:

Eric-XPS:~$   lsusb Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 002: ID 0b95:7720 ASIX Electronics Corp. AX88772 Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 0c45:670c Microdia  Bus 001 Device 002: ID 0cf3:e300 Atheros Communications, Inc.  Bus 001 Device 007: ID 0951:1665 Kingston Technology Digital DataTraveler SE9 64GB Bus 001 Device 005: ID 1c4f:0026 SiGma Micro Keyboard Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub 

What do you suggest to troubleshoot and, ultimately, get this working?

Ubuntu 18.04 Boot freezes at “Started Hold until boot finishes up”

I’m currently using my old windows computer to post, because I’ve caused a boot process issue on my ubuntu 18.04 computer. The problem started when I was trying to figure out how to remap my right control key (which I use often but was broken) onto my right alt key. I had read online that people recommended editing the xkb file to remap keys. After I edited the lines concerning control and alt, I restarted my computer and found that the boot process froze at the line “Started Hold until boot finishes up”. I left it on overnight thinking it might finish, but nothing changed.

I also tried restarting a few times, as well as using the grub menu options like repair and clean, but nothing helped. Lastly I tried some of the solutions from other topics with similar problems, but they didn’t help either. One of the solutions was to remove snapd, which I did but that just made the boot process list longer.

I have access to the recovery mode, grub menu and F2/F3, but I’m new to linux so I don’t know any troubleshooting commands that can help. If I caused this issue by messing with the xkb file, does anyone know any terminal commands to revert the file to its original script? I know windows had a recovery option to revert the system back to an earlier state (which I had used when I messed around with the registry and broke stuff on my win 7). Does ubuntu have any option or command that can do something similar? Attached below is the screen that my computer freezes on.

Thank you all very much for your time and any advice you can offer me to fix this issue. I will try to reply as soon as I can to any questions posted; though I might be delayed due to my job.Ubuntu 18.04 boot freeze screen image

virtualized Ubuntu 18.04 on VMware Workstation Pro fails to mount drive on physical Windows 10 host

I want to share files between an app on a native Windows 10 and an app on virtualized Ubuntu on VMware Workstation Pro, but can’t mount the Windows 10 shared directory onto Ubuntu with this Linux command:

sudo mount -t cifs //192.168.7.24/demo /home/movano/Desktop/share/ -o username=me,uid=me,password=pw

However, a 2nd laptop running Ubuntu 18.04 natively can mount the same directory on the same Windows 10 laptop OK. So, the problem is not on Windows. Samba smb.conf

Workflow…
Installed VMware Workstation Pro onto Windows 10 and virtualized Ubuntu 18.04
Installed Samba on the virtualized Ubuntu with these commands:
sudo apt install samba -y
sudo systemctl restart smbd

This newly installed smb.conf is identical to the smb.conf on the 2nd laptop with native Ubuntu, which of course also has Samba.

Have tried Network Adapter NAT, bridge, and host-only, but all get same problem.

Ubuntu 18.04: Ethernet keeps dropping randomly for several seconds

Recently I have installed a new router because of a internet provider change and since then my previously faithful ethernet connection makes problems. Even though internet access and the network in general works, the ethernet connection fails every now and then for several seconds. It seems to happen preferably when starting large/fast downloads but will also happen while doing things not obviously network related.

Here are my hardware specs:

julian@julian-desktop:~$   lspci -nnk | grep -i net -A2 24:00.0 Network controller [0280]: Intel Corporation Dual Band Wireless-AC 3168NGW [Stone Peak] [8086:24fb] (rev 10)     Subsystem: Intel Corporation Device [8086:2110]     Kernel driver in use: iwlwifi -- 25:00.0 Ethernet controller [0200]: Intel Corporation I211 Gigabit Network Connection [8086:1539] (rev 03)     Subsystem: ASRock Incorporation I211 Gigabit Network Connection [1849:1539]     Kernel driver in use: igb     Kernel modules: igb 

And ifconfig:

julian@julian-desktop:~$   ifconfig enp37s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500         inet 192.168.178.42  netmask 255.255.255.0  broadcast 192.168.178.255         inet6 fe80::4a89:a9d2:49ca:9df4  prefixlen 64  scopeid 0x20<link>         ether 70:85:c2:a8:bb:7f  txqueuelen 1000  (Ethernet)         RX packets 333573  bytes 479511002 (479.5 MB)         RX errors 2  dropped 0  overruns 0  frame 1         TX packets 180965  bytes 14125591 (14.1 MB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0         device memory 0xf7500000-f751ffff    enp3s0f0u3c4i2: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500         ether 42:33:1a:65:b8:0c  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  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  (Lokale Schleife)         RX packets 6415  bytes 586547 (586.5 KB)         RX errors 0  dropped 0  overruns 0  frame 0         TX packets 6415  bytes 586547 (586.5 KB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0  wlp36s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500         inet 10.42.0.1  netmask 255.255.255.0  broadcast 10.42.0.255         inet6 fe80::d7d4:24b5:9682:47bb  prefixlen 64  scopeid 0x20<link>         ether 3c:6a:a7:4e:40:f8  txqueuelen 1000  (Ethernet)         RX packets 104  bytes 11975 (11.9 KB)         RX errors 0  dropped 1  overruns 0  frame 0         TX packets 303  bytes 47366 (47.3 KB)         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0 

And here is the log from /var/log/syslog one of the disconnection periods:

Apr 15 17:52:46 julian-desktop kernel: [ 1657.601916] igb 0000:25:00.0 enp37s0: igb: enp37s0 NIC Link is Down Apr 15 17:52:52 julian-desktop wpa_supplicant[1338]: message repeated 21 times: [ wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1] Apr 15 17:52:52 julian-desktop NetworkManager[1320]: <info>  [1555343572.1914] device (enp37s0): state change: activated -> unavailable (reason 'carrier-changed', sys-iface-state: 'managed') Apr 15 17:52:52 julian-desktop NetworkManager[1320]: <info>  [1555343572.2074] dhcp4 (enp37s0): canceled DHCP transaction, DHCP client pid 4430 Apr 15 17:52:52 julian-desktop NetworkManager[1320]: <info>  [1555343572.2074] dhcp4 (enp37s0): state changed bound -> done Apr 15 17:52:52 julian-desktop avahi-daemon[1334]: Withdrawing address record for 192.168.178.42 on enp37s0. Apr 15 17:52:52 julian-desktop avahi-daemon[1334]: Leaving mDNS multicast group on interface enp37s0.IPv4 with address 192.168.178.42. Apr 15 17:52:52 julian-desktop avahi-daemon[1334]: Interface enp37s0.IPv4 no longer relevant for mDNS. Apr 15 17:52:52 julian-desktop avahi-daemon[1334]: Withdrawing address record for fe80::4a89:a9d2:49ca:9df4 on enp37s0. Apr 15 17:52:52 julian-desktop avahi-daemon[1334]: Leaving mDNS multicast group on interface enp37s0.IPv6 with address fe80::4a89:a9d2:49ca:9df4. Apr 15 17:52:52 julian-desktop avahi-daemon[1334]: Interface enp37s0.IPv6 no longer relevant for mDNS. Apr 15 17:52:52 julian-desktop NetworkManager[1320]: <info>  [1555343572.2104] manager: NetworkManager state is now CONNECTED_SITE Apr 15 17:52:52 julian-desktop NetworkManager[1320]: <info>  [1555343572.2111] manager: NetworkManager state is now CONNECTED_LOCAL Apr 15 17:52:52 julian-desktop dbus-daemon[1302]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service' requested by ':1.13' (uid=0 pid=1320 comm="/usr/sbin/NetworkManager --no-daemon " label="unconfined") Apr 15 17:52:52 julian-desktop whoopsie[2042]: [17:52:52] offline Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:52:52 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:52:52 julian-desktop systemd[1]: Starting Network Manager Script Dispatcher Service... Apr 15 17:52:52 julian-desktop deja-dup-monito[3587]: Source ID 112 was not found when attempting to remove it Apr 15 17:52:52 julian-desktop gsd-sharing[2454]: Failed to StopUnit service: GDBus.Error:org.freedesktop.systemd1.NoSuchUnit: Unit gnome-user-share-webdav.service not loaded. Apr 15 17:52:52 julian-desktop gsd-sharing[2454]: Failed to StopUnit service: GDBus.Error:org.freedesktop.systemd1.NoSuchUnit: Unit rygel.service not loaded. Apr 15 17:52:52 julian-desktop dbus-daemon[1302]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Apr 15 17:52:52 julian-desktop gsd-sharing[2454]: Failed to StopUnit service: GDBus.Error:org.freedesktop.systemd1.NoSuchUnit: Unit gnome-remote-desktop.service not loaded. Apr 15 17:52:52 julian-desktop systemd[1]: Started Network Manager Script Dispatcher Service. Apr 15 17:52:52 julian-desktop nm-dispatcher: req:1 'connectivity-change': new request (1 scripts) Apr 15 17:52:52 julian-desktop nm-dispatcher: req:1 'connectivity-change': start running ordered scripts... Apr 15 17:52:52 julian-desktop nm-dispatcher: req:2 'down' [enp37s0]: new request (1 scripts) Apr 15 17:52:52 julian-desktop nm-dispatcher: req:2 'down' [enp37s0]: start running ordered scripts... Apr 15 17:52:53 julian-desktop wpa_supplicant[1338]: wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1 Apr 15 17:52:53 julian-desktop goa-daemon[2337]: goa_http_client_check() failed: 2 — Fehler beim Auflösen von »kmu.files.cnow.at«: Der Name oder der Dienst ist nicht bekannt Apr 15 17:52:53 julian-desktop goa-daemon[2337]: /org/gnome/OnlineAccounts/Accounts/account_1547674158_0: Setting AttentionNeeded to TRUE because EnsureCredentials() failed with: Ungültiges Passwort für Benutzer »julian.fesel@inode.at« (goa-error-quark, 0): Rechnername konnte nicht aufgelöst werden (goa-error-quark, 4) Apr 15 17:52:54 julian-desktop wpa_supplicant[1338]: wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1 Apr 15 17:52:54 julian-desktop goa-daemon[2337]: goa_http_client_check() failed: 2 — Fehler beim Auflösen von »kmu.files.cnow.at«: Der Name oder der Dienst ist nicht bekannt Apr 15 17:52:55 julian-desktop wpa_supplicant[1338]: wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1 Apr 15 17:53:06 julian-desktop wpa_supplicant[1338]: message repeated 11 times: [ wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1] Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8275] device (enp37s0): carrier: link connected Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8279] device (enp37s0): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed') Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8291] policy: auto-activating connection 'Kabelgebundene Verbindung 1' Apr 15 17:53:06 julian-desktop kernel: [ 1678.238273] igb 0000:25:00.0 enp37s0: igb: enp37s0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: RX/TX Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8307] device (enp37s0): Activation: starting connection 'Kabelgebundene Verbindung 1' (599cf1b6-92de-3ca4-a47a-a9b8f9c1b24f) Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8310] device (enp37s0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed') Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8313] manager: NetworkManager state is now CONNECTING Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8318] device (enp37s0): state change: prepare -> config (reason 'none', sys-iface-state: 'managed') Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8325] device (enp37s0): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed') Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8329] dhcp4 (enp37s0): activation: beginning transaction (timeout in 45 seconds) Apr 15 17:53:06 julian-desktop NetworkManager[1320]: <info>  [1555343586.8347] dhcp4 (enp37s0): dhclient started with pid 4755 Apr 15 17:53:06 julian-desktop dhclient[4755]: DHCPREQUEST of 192.168.178.42 on enp37s0 to 255.255.255.255 port 67 (xid=0x6d294be5) Apr 15 17:53:07 julian-desktop wpa_supplicant[1338]: wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1 Apr 15 17:53:08 julian-desktop wpa_supplicant[1338]: wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1 Apr 15 17:53:08 julian-desktop goa-daemon[2337]: goa_http_client_check() failed: 2 — Fehler beim Auflösen von »kmu.files.cnow.at«: Der Name oder der Dienst ist nicht bekannt Apr 15 17:53:08 julian-desktop avahi-daemon[1334]: Joining mDNS multicast group on interface enp37s0.IPv6 with address fe80::4a89:a9d2:49ca:9df4. Apr 15 17:53:08 julian-desktop avahi-daemon[1334]: New relevant interface enp37s0.IPv6 for mDNS. Apr 15 17:53:08 julian-desktop avahi-daemon[1334]: Registering new address record for fe80::4a89:a9d2:49ca:9df4 on enp37s0.*. Apr 15 17:53:09 julian-desktop wpa_supplicant[1338]: wlp36s0: CTRL-EVENT-SCAN-FAILED ret=-95 retry=1 Apr 15 17:53:09 julian-desktop dhclient[4755]: DHCPREQUEST of 192.168.178.42 on enp37s0 to 255.255.255.255 port 67 (xid=0x6d294be5) Apr 15 17:53:09 julian-desktop dhclient[4755]: DHCPACK of 192.168.178.42 from 192.168.178.1 Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1435] dhcp4 (enp37s0):   address 192.168.178.42 Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1435] dhcp4 (enp37s0):   plen 24 (255.255.255.0) Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1435] dhcp4 (enp37s0):   gateway 192.168.178.1 Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1435] dhcp4 (enp37s0):   lease time 864000 Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1435] dhcp4 (enp37s0):   nameserver '192.168.178.1' Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1435] dhcp4 (enp37s0):   domain name 'fritz.box' Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1436] dhcp4 (enp37s0): state changed unknown -> bound Apr 15 17:53:09 julian-desktop avahi-daemon[1334]: Joining mDNS multicast group on interface enp37s0.IPv4 with address 192.168.178.42. Apr 15 17:53:09 julian-desktop avahi-daemon[1334]: New relevant interface enp37s0.IPv4 for mDNS. Apr 15 17:53:09 julian-desktop avahi-daemon[1334]: Registering new address record for 192.168.178.42 on enp37s0.IPv4. Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1456] device (enp37s0): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed') Apr 15 17:53:09 julian-desktop dhclient[4755]: bound to 192.168.178.42 -- renewal in 360679 seconds. Apr 15 17:53:09 julian-desktop whoopsie[2042]: [17:53:09] Cannot reach: https://daisy.ubuntu.com Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1466] device (enp37s0): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed') Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1469] device (enp37s0): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed') Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1471] manager: NetworkManager state is now CONNECTED_LOCAL Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1487] manager: NetworkManager state is now CONNECTED_SITE Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1488] policy: set 'Kabelgebundene Verbindung 1' (enp37s0) as default for IPv4 routing and DNS Apr 15 17:53:09 julian-desktop NetworkManager[1320]: <info>  [1555343589.1492] device (enp37s0): Activation: successful, device activated. Apr 15 17:53:09 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:53:09 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:53:09 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:53:09 julian-desktop dbus-daemon[1302]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service' requested by ':1.13' (uid=0 pid=1320 comm="/usr/sbin/NetworkManager --no-daemon " label="unconfined") Apr 15 17:53:09 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Cache geleert Apr 15 17:53:09 julian-desktop dnsmasq[1846]: lese /etc/resolv.conf Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Benutze Namensserver 127.0.0.53#53 Apr 15 17:53:09 julian-desktop dnsmasq[1846]: Cache geleert 

I am fairly certain that the problem is ubuntu/pc related and that connection cable and router are fine. I tried using the same cable connection with another computer and there I don’t experiance any problems. I also already updated the system but it makes no difference.

I am not really a ubuntu superuser and kind of at a loss on how to solve/start solving this issue (with the exception of drastic measures like reinstalling the system). Please let me know if I can provide any additional info.

Problem displaying pdf files after update to lubuntu 18.04

Recently I updated my lubuntu version from 16.04 to 18.04 and since then I have had issues displaying certain symbols pdf plots (using evince). The pdf file I am trying to display is the following:

https://www.dropbox.com/s/mc2wp2y8q2af1vj/stupidPlot.pdf?dl=0

On my screen it appears as in the following screenshot:

wrong_display

while it should appear as follows:

correct_display

So the greek symbols delta, gamma and capital delta are not displayed as expected. After some searching I suppose it must be related to the fact that the fonts are not embedded in the pdf file I am trying to read (though I am not sure, so correct me if this is not the case). pdffonts gives the following output:

name                                 type              encoding         emb sub uni object ID ------------------------------------ ----------------- ---------------- --- --- --- --------- Times-Italic                         Type 1            WinAnsi          no  no  no       7  0 Times-Bold                           Type 1            WinAnsi          no  no  no       8  0 Times-BoldItalic                     Type 1            WinAnsi          no  no  no       9  0 Helvetica                            Type 1            WinAnsi          no  no  no      10  0 Helvetica-Oblique                    Type 1            WinAnsi          no  no  no      11  0 Helvetica-Bold                       Type 1            WinAnsi          no  no  no      12  0 Helvetica-BoldOblique                Type 1            WinAnsi          no  no  no      13  0 Courier                              Type 1            WinAnsi          no  no  no      14  0 Courier-Oblique                      Type 1            WinAnsi          no  no  no      15  0 Courier-Bold                         Type 1            WinAnsi          no  no  no      16  0 Courier-BoldOblique                  Type 1            WinAnsi          no  no  no      17  0 Symbol                               Type 1            Symbol           no  no  no      18  0 Times-Roman                          Type 1            WinAnsi          no  no  no      19  0 ZapfDingbats                         Type 1            ZapfDingbats     no  no  no      20  0 Symbol                               Type 1            Symbol           no  no  no      21  0 

I tried to fix it using the suggestion given on: https://stackoverflow.com/questions/10277418/the-pdf-viewer-evince-on-linux-can-not-display-some-math-symbols-correctly to run GhostScript as follows:

gs -o gs-repaired—stupidPlot.pdf -dPDFSETTINGS=/prepress -sDEVICE=pdfwrite stupidPlot.pdf

which does not seem to work and gives the error:

   **** Error: Encountered 'obj' while expecting 'endobj'.                Treating this as a missing 'endobj', output may be incorrect.    **** Error: Encountered 'obj' while expecting 'endobj'.                Treating this as a missing 'endobj', output may be incorrect. Processing pages 1 through 1. Page 1 Loading NimbusSans-Regular font from /usr/share/ghostscript/9.26/Resource/Font/NimbusSans-Regular... 5086732 3571608 2679472 1286852 4 done. Loading StandardSymbolsPS font from /usr/share/ghostscript/9.26/Resource/Font/StandardSymbolsPS... 5119500 3664456 2699672 1302649 4 done.     **** This file had errors that were repaired or ignored.    **** Please notify the author of the software that produced this    **** file that it does not conform to Adobe's published PDF    **** specification. 

**** The rendered output from this file may be incorrect.

Moreover I have to produce many (tens of) thousands of pdf plots, so it would be preferable not to have to embed fonts in them in order to display them correctly.

So I wonder if anyone knows what might have changed when updating from lubuntu 16.04 to 18.04 (in 16.04 the plots were always correctly displayed), and how I could correctly display the pdf’s in evince, preferably without having to embed the fonts in the pdf.

I also tried using xpdf and okular as alternatives to evince, but they displayed the symbols wrongly in the same manner.

How to install PCL on Ubuntu 18.04

CMake Error at cv_utils/CMakeLists.txt:8 (find_package):   By not providing "FindPCL.cmake" in CMAKE_MODULE_PATH this project has   asked CMake to find a package configuration file provided by "PCL", but   CMake did not find one.    Could not find a package configuration file provided by "PCL" with any of   the following names:      PCLConfig.cmake     pcl-config.cmake    Add the installation prefix of "PCL" to CMAKE_PREFIX_PATH or set "PCL_DIR"   to a directory containing one of the above files.  If "PCL" provides a   separate development package or SDK, be sure it has been installed.   -- Configuring incomplete, errors occurred! See also "/home/ahmad/Desktop/Layered Scene Decomposition/LayeredSceneDecomposition-master/build/CMakeFiles/CMakeOutput.log".