Ubuntu Archives - Page 6 of 6

Run a script on boot using systemd on Ubuntu 18.04

Previous versions of Ubuntu had /etc/rc.local. that get executed after system boot.

On Ubuntu 18.04, you can use systemd to start a bash script on system boot.

Create file

vi /etc/systemd/system/sok-startup.service

Add

[Unit]
Description=Start up script
ConditionPathExists=/etc/rc.local

[Service]
Type=forking
ExecStart=/etc/rc.local start
TimeoutSec=0
StandardOutput=tty
RemainAfterExit=yes
SysVStartPriority=99

[Install]
WantedBy=multi-user.target

Create file /etc/rc.local with

#!/bin/bash

touch /root/OK

exit 0

You can replace “touch /root/OK” with whatever command you need to execute.

Make it executable with

chmod 755 /etc/rc.local

Reload systemd

systemctl daemon-reload

Enable the service

systemctl enable sok-startup.service

Now reboot the server, you will see /root/OK get created.

May 12, 2019

Install AnyDesk on Ubuntu using flatpak

AnyDesk is a remote desktop sharing application like TeamViewer and Google Remote Desktop. I normally use Google Chrome Remote desk as it is completely free. TeamViewer is popuplar alternative, but if they found out you are using it more often, they will limit your session to 5 minutes, some times even less to force you pay for paid version.

AnyDesk available for Ubuntu in deb file. I don’t like installing .deb package as it run a background process on port 7070 or somthing like that. So i decided to go with flatpak version.

First install flatpak with command

sudo apt install flatpak

Add remote

flatpak remote-add --if-not-exists flathub https://flathub.org/repo/flathub.flatpakrepo

Now you can install AnyDesk with command

flatpak install flathub com.anydesk.Anydesk

To run AnyDesk, run

flatpak run com.anydesk.Anydesk

May 2, 2019

Configure Failover IP in Ubuntu 18.04 OVH VPS

Default /etc/network/interfaces in Ubuntu 18.04 in OVH VPS look like following. Click here for Ubuntu 20.04 instructions.

root@vps624512:~# cat /etc/network/interfaces 
# ifupdown has been replaced by netplan(5) on this system.  See
# /etc/netplan for current configuration.
# To re-enable ifupdown on this system, you can run:
#    sudo apt install ifupdown
root@vps624512:~#

First install

sudo apt install ifupdown -y

Configure Main IP

use “ip a” command to find out interface name and IP of the VPS

root@vps624512:~# ip a
1: lo:  mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens3:  mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether fa:16:3e:f4:1e:fd brd ff:ff:ff:ff:ff:ff
    inet 51.77.149.182/32 scope global dynamic ens3
       valid_lft 49349sec preferred_lft 49349sec
    inet6 fe80::f816:3eff:fef4:1efd/64 scope link 
       valid_lft forever preferred_lft forever
root@vps624512:~#

In this case,

IP = 51.77.149.182
Interface Name = ens3

Use “route -n” command to find out gateway.

root@vps624512:~# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         51.77.148.1     0.0.0.0         UG    100    0        0 ens3
51.77.148.1     0.0.0.0         255.255.255.255 UH    100    0        0 ens3
root@vps624512:~#

GATEWAY = 51.77.148.1

Edit /etc/network/interfaces

vi /etc/network/interfaces

Add following

auto INTERFACE_NAME
iface INTERFACE_NAME inet static
    address SEVER_MAIN_IP
    netmask 255.255.255.255
    broadcast SEVER_MAIN_IP
    dns-nameservers 8.8.8.8 1.1.1.1
    post-up route add GATEWAY_IP dev INTERFACE_NAME
    post-up route add default gw GATEWAY_IP
    post-down route del default gw GATEWAY_IP
    post-down route del GATEWAY_IP dev INTERFACE_NAME

In the above, replace INTERFACE_NAME, SEVER_MAIN_IP and GATEWAY_IP.

For this server, i added.

auto ens3
iface ens3 inet static
    address 51.77.149.182
    netmask 255.255.255.255
    broadcast 51.77.149.182
    post-up route add 51.77.148.1 dev ens3
    post-up route add default gw 51.77.148.1
    post-down route del default gw 51.77.148.1
    post-down route del 51.77.148.1 dev ens3

Now reboot the server.

Once server is back online, you can configure failover IPS.

Configure Failover IP

Use following script to generate your config, add in end of /etc/network/inferfaces file

php script to generate ip config

Once configured, you need to reboot the servr.

Verify IP is up with fping command.

fping
/etc/inetnet/interfaces

February 16, 2019

Ubuntu Slow Boot

Last day my PC become very slow to boot.

boby@ok-pc-01:~$ systemd-analyze 
Startup finished in 15.777s (kernel) + 3min 1.400s (userspace) = 3min 17.178s
graphical.target reached after 1min 47.169s in userspace
boby@ok-pc-01:~$

It take 3 minutes and 17 seconds to boot up.

This happend after i did some changes to my 2nd hard disk and added ZFS partition. First thing i thought it was ZFS that make my PC slow.

systemd-analyze blame did not show any useful info.

systemd-analyze blame

To find the problem, i edited the file

sudo  vi /etc/defaults/grub

Find the line

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

Replace it with

GRUB_CMDLINE_LINUX_DEFAULT=""

Now rebuild grub.cfg with

update-grub2

Rebooted the PC. Now instead of showing Ubuntu splash screen, you get lot of text, that shows what actually your PC is doing.

From the boot message i found system waiting 1 minutes 30 seconds for mounting one of the disk partition. This is because i re-partitioned my 2nd hard disk and forget to remove the disk from /etc/fstab.

I removed the non existant disk entry from /etc/fstab and rebooted PC. Now it boot much faster.

See Ubuntu

June 22, 2018

Enable Native Notification in Google Chrome

UPDATE: Google Chrome have this option removed now. But you still can manually enable it by editing config file. See Disable Native Notification on Google Chrome Ubuntu

To enable/disable native notification in Google chrome, go to

chrome://flags/#enable-native-notifications

Once native notification is enabled/disabled, you will be asked to restart browser.

On Ubuntu 18.04, i disable Native Notification as it is buggy, come can’t control how long notification shown if you use native notification. With chrome provided notification, you can use javascript to disable notification after predefined time. On Ubuntu 16.04, native notification is disabled by default.

Chrome

June 13, 2018

Install x2Go Client in Ubuntu

x2go client is available in Ubuntu repoitory. To install, run

apt install x2goclient

Here are some useful shortcuts

Ctrl + Alt + F = Switch between full screen and window mode
Ctrl + Alt + arrow keys = change view port.

x2go

June 12, 2018

Ubuntu

do-release-upgrade – upgrade Ubuntu to the next release. If you are using Ubuntu 20.04 LTS, it will upgrade to 22.04 LTS.

Ubuntu Desktop

Ubuntu 18.04

March 28, 2018

OVH VPS Configure failover IP in Ubuntu

On Ubuntu

Default config look like

root@zecurecode:~# cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# Source interfaces
# Please check /etc/network/interfaces.d before changing this file
# as interfaces may have been defined in /etc/network/interfaces.d
# See LP: #1262951
source /etc/network/interfaces.d/*.cfg

root@zecurecode:~#

/etc/network/interfaces.d/50-cloud-init.cfg is used to auto configure network interface with dhcp.

root@zecurecode:~# cat /etc/network/interfaces.d/50-cloud-init.cfg 
# This file is generated from information provided by
# the datasource.  Changes to it will not persist across an instance.
# To disable cloud-init's network configuration capabilities, write a file
# /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following:
# network: {config: disabled}
auto lo
iface lo inet loopback

auto ens3
iface ens3 inet dhcp
root@zecurecode:~#

First find the gateway used by the VPS.

root@zecurecode:~# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         51.254.32.1     0.0.0.0         UG    0      0        0 ens3
51.254.32.1     0.0.0.0         255.255.255.255 UH    0      0        0 ens3
root@zecurecode:~#

We found the gateway IP 51.254.32.1

The VPS had main IP of the server is 51.254.35.58 and secondary IPS 94.23.153.137, 178.32.52.159, 178.32.49.157

Here is the modified /etc/network/interfaces

root@zecurecode:~# cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# Source interfaces
# Please check /etc/network/interfaces.d before changing this file
# as interfaces may have been defined in /etc/network/interfaces.d
# See LP: #1262951
#source /etc/network/interfaces.d/*.cfg

auto ens3
iface ens3 inet static
    address 51.254.35.58
    netmask 255.255.255.255
    broadcast 51.254.35.58
    post-up route add 51.254.32.1 dev ens3
    post-up route add default gw 51.254.32.1
    post-down route del default gw 51.254.32.1
    post-down route del 51.254.32.1 dev ens3

auto ens3:1
iface ens3:1 inet static
    address 94.23.153.137
    netmask 255.255.255.255
    broadcast 94.23.153.137

auto ens3:2
iface ens3:2 inet static
    address 178.32.52.159
    netmask 255.255.255.255
    broadcast 178.32.52.159

auto ens3:3
iface ens3:3 inet static
    address 178.32.49.157
    netmask 255.255.255.255
    broadcast 178.32.49.157


root@zecurecode:~#

Here is a PHP script to create OVH failover IP config for Ubuntu/Debian.

https://gist.github.com/serverok/991f7ccd1be36cbc579e8d55caf39715

January 14, 2018

getting huawei e8231 work on ubuntu 14.04

After connecting, i get following in lsusb

root@fwhlin:~ # lsusb | grep 12d1
Bus 009 Device 004: ID 12d1:1f01 Huawei Technologies Co., Ltd. E353/E3131 (Mass storage mode)
root@fwhlin:~ #

It says “Mass storage mode”. If you check demesg, you will see

[ 2385.775523] usb 9-2: New USB device found, idVendor=12d1, idProduct=1f01
[ 2385.775527] usb 9-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2385.775529] usb 9-2: Product: HUAWEI Mobile
[ 2385.775531] usb 9-2: Manufacturer: HUAWEI
[ 2385.775532] usb 9-2: SerialNumber: FFFFFFFFFFFFFFFF
[ 2385.837882] usb-storage 9-2:1.0: USB Mass Storage device detected
[ 2385.838108] scsi15 : usb-storage 9-2:1.0
[ 2386.858462] scsi 15:0:0:0: CD-ROM            HUAWEI   Mass Storage     2.31 PQ: 0 ANSI: 2
[ 2386.859826] sr1: scsi-1 drive
[ 2386.859946] sr 15:0:0:0: Attached scsi CD-ROM sr1

Last line says, device mounted as “/dev/sr1”

root@fwhlin:~ # df -h | grep sr
/dev/sr1        4.3M  4.3M     0 100% /media/boby/MobileWiFi
root@fwhlin:~ #

Changing Device Mode to Modem

I found some information about the device in file

sudo -s
cd /usr/share/usb_modeswitch
tar zxvf configPack.tar.gz

root@fwhlin:~ # cat /usr/share/usb_modeswitch/12d1:1f01
# Huawei E353 (3.se) and others
TargetVendor=0x12d1
TargetProductList="14db,14dc"
MessageContent="55534243123456780000000000000011062000000101000100000000000000"
NoDriverLoading=1
root@fwhlin:~ #

It says device can operate as products “14db” and “14dc”.

I tried changing device mode to product id 14db, it did not work, so tried 14dc and it worked.

usb_modeswitch -v 12d1 -p 1f01 -V 12d1 -P 14dc -M "55534243123456780000000000000011062000000101000100000000000000"

root@fwhlin:~ # usb_modeswitch -v 12d1 -p 1f01 -V 12d1 -P 14dc -M "55534243123456780000000000000011062000000101000100000000000000"
Look for target devices ...
 No devices in target mode or class found
Look for default devices ...
   product ID matched
 Found devices in default mode (1)
Access device 002 on bus 009
Current configuration number is 1
Use interface number 0
Use endpoints 0x01 (out) and 0x81 (in)

USB description data (for identification)
-------------------------
Manufacturer: HUAWEI
     Product: HUAWEI Mobile
  Serial No.: FFFFFFFFFFFFFFFF
-------------------------
Looking for active driver ...
 No active driver found. Detached before or never attached
Set up interface 0
Use endpoint 0x01 for message sending ...
Trying to send message 1 to endpoint 0x01 ...
 OK, message successfully sent
Reset response endpoint 0x81
Reset message endpoint 0x01
-> Run lsusb to note any changes. Bye!

root@fwhlin:~ #

Now “ifconfig” shows usb0.

root@fwhlin:~ # ifconfig
...
...
...
usb0      Link encap:Ethernet  HWaddr be:69:7c:b1:a3:b6  
          inet addr:192.168.8.100  Bcast:192.168.8.255  Mask:255.255.255.0
          inet6 addr: fe80::bc69:7cff:feb1:a3b6/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:15 errors:0 dropped:0 overruns:0 frame:0
          TX packets:44 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:6315 (6.3 KB)  TX bytes:8138 (8.1 KB)

root@fwhlin:~ #

If you check “lsusb”, now device have different product id.

root@fwhlin:~ # lsusb | grep 12d1
Bus 009 Device 003: ID 12d1:14dc Huawei Technologies Co., Ltd. 
root@fwhlin:~ #

Connecting To Internet

You will need to disable eth0 or all traffic will be routed through it by default.

suo ifconfig eth0 down

root@fwhlin:~ # curl http://iptools.bizhat.com/ipv4.php
59.98.137.87
root@fwhlin:~ # sudo ifconfig eth0 down
root@fwhlin:~ # curl http://iptools.bizhat.com/ipv4.php
106.77.164.191
root@fwhlin:~ #

December 19, 2015

Tag: Ubuntu

Ubuntu Desktop

Ubuntu 18.04

Changing Device Mode to Modem

Connecting To Internet