MYSQL cluster issue: shutdown data node correctly breaks replication

I faced issue on mysql cluster (5.7.28), i shuted down properly vm6 (data nodes) and the mysql replication was broken, i’m trying to make the link bettwen the datanode down and the replication broken but i still can’t find the reason (below the relevant), is there someone who can help me to find the link

Slave: Got error 4009 ‘Cluster Failure’ from NDB Error_code: 1296 [Warning] Slave: Can’t lock file (errno: 157 – Could not connect to storage engine) Error_code: 1015 Error running query, slave SQL thread aborted. Fix the problem, and restart the slave SQL thread with "SLAVE START".

Ubuntu 18.04 cannot shutdown my laptop

Please help me solve this problem. I have HP Notebook 15 laptop from 2014. Recently I have installed Ubuntu 18.04. The only problem I have is that the OS cannot shutdown mu laptop and I have to force shutdown with the power off button. I have tried many solutions on the internet like modifying the /etc/default/grub ; I have tried via linux terminal and through the GUI. I have tried Linux Mint Tina, Ubuntu 16 lts and Ubuntu 19 and nothing worked it just freezes at shutting down.

Ubuntu 16.04 freezes at Shutdown and restart

Im shashikanth from India. i have reinstalled Ubuntu 16.04 via USB pendrive in DELL Inspiron 15 7577 system. Ubuntu OS doesn’t shut down normally after re-installation. I have to forcefully press the shutdown button for it. I have seen this below links and tried to rectify the error and resolve it but it didn’t work out.

My Ubuntu won't shutdown

Ubuntu 16.04 hangs on shutdown/restart

i tried to install nvidia drivers manually but the screen freezes for this step also.

Can Any Help me resolve this issue asap

Thank you

Kik to shutdown all it’s services.

Do you use the chat app Kik? Then we have bad news when the app's developer decided to close down the chat app. This is because of a very close relationship with the US Securities and Exchange Commission (SEC), which put Kik in the wheel of the release of their cryptocurrency Kin.

The app will be closed and just over a hundred employees developers will get rid of their jobs and only a core team of 19 people will remain and continue to work with Kin.

What do you think about this?

Ubuntu 19.04 restart after shutdown

I have installed Ubuntu 19.04, And I have an issue that Ubuntu Automatically restart after I shut down my laptop.

Ubuntu: 19.04, Machine: Acer V5-471, *single boot

I have tried everything on the internet.

Some solution on the internet I tried, But nothing works πŸ™

Ubuntu 16 reboots seconds after shutdown

https://ubuntuforums.org/showthread.php?t=2188726

https://ubuntuforums.org/showthread.php?t=2390730

Ubuntu 18.04 restarting by itself after shutdown

I know there are already plenty questions here related to this one, but I can’t find an answer which solves my problem.

I’ve installed a fresh Ubuntu 18.04 on a Dell Optiplex 9020 SFF. And now I’m trying to make WOL – Wake On Lan – working. The first step I’ve done was to activate WOL in BIOS and deactivate Deep Sleep. And it seems to just work as expected.

I can shutdown PC and wake it up with a magic packet (and do it an unlimited number of times).

But if I choose to restart/reboot, the PC will do it normally and then if I try to shut it down (with the button on the top-right of the screen (or with a shutdown now, shutdown -H now) it will shutdown, wait 3 seconds, and then reboot by itself. The only way to shut it down is to long press the hardware power button. And then it reworks as expected (with WOL) until the next reboot/restart is issued.

I’ve tried several things in /etc/default/grub like adding acpi=force apm=power_off or noapic or reboot=a,w followed by an update-grub. I’ve also updated my BIOS to latest version (A25). But nothing works.

I think the problem is when I trigger a reboot, something change somewhere and make following shutdown working a bit differently and cause computer to reboot by itself.

I’ve maybe a clue after investigating journalctl. When I trigger a normal shutdown (without a reboot before):

sept. 07 00:57:28 barbie systemd[1]: Reached target Shutdown. sept. 07 00:57:28 barbie systemd[1]: Reached target Final Step. sept. 07 00:57:28 barbie systemd[1]: Starting Power-Off... sept. 07 00:57:28 barbie systemd[1]: Shutting down. sept. 07 00:57:28 barbie kernel: printk: systemd-shutdow: 40 output lines suppressed due to ratelimiting sept. 07 00:57:28 barbie systemd-shutdown[1]: Syncing filesystems and block devices. sept. 07 00:57:28 barbie systemd-shutdown[1]: Sending SIGTERM to remaining processes... sept. 07 00:57:28 barbie systemd-journald[431]: Journal stopped 

And when I trigger a shutdown (with a reboot before):

sept. 07 00:59:08 barbie systemd[1]: Reached target Shutdown. sept. 07 00:59:08 barbie systemd[1]: Reached target Final Step. sept. 07 00:59:08 barbie systemd[1]: Starting Power-Off... sept. 07 00:59:08 barbie systemd[1]: Shutting down. sept. 07 00:59:08 barbie kernel: printk: systemd-shutdow: 39 output lines suppressed due to ratelimiting sept. 07 00:59:08 barbie systemd-shutdown[1]: Syncing filesystems and block devices. sept. 07 00:59:08 barbie systemd-journald[426]: Journal stopped 

Note the missing line: systemd-shutdown[1]: Sending SIGTERM to remaining processes... Maybe it explains why the computer reboot by itself ?

That’s all I’ve done so far. Your clues/ideas are welcome. Thanks!

How can I fix the sudden shutdown of Android device when USB tethering on Lubuntu 18.04?

I have experienced 2 problems for USB tethering on Lubuntu 18.04 First: I try to USB tethering from Android 4.4.4 Samsung Galaxy Grand smartphone to Lubuntu 18.04 32-bit desktop computer but Android device asks me PIN code for SIM card a few second after connecting USB cable. And then Android device chills although I enter the PIN code. And I have to disconnect USB cable and reboot the Android device. Second: I try to USB tethering from Android 5.1.1 Everest tablet to Lubuntu 18.04 64- bit desktop computer. As soon as connecting, tablet suddenly restarts. and so I failed tethering. Is there any way to cope with these vexing problems ? Thank you.

Erase /home/ from casper-rw overlay on shutdown (systemd service)

In my company we use a USB bootable live stick with Ubuntu (erm… Xubuntu) 18.04 to do job interviews. It has a bunch of tools (three or four IDEs, a couple of database GUI viewers…) and a toy project to ask questions about.

That USB stick has a Casper-RW overlay partition for persistent storage (created with mkusb). Said partition is mostly used to store Docker images and to keep some start-up values that can change a bit depending on which machine the stick is plugged into.

That partition is mounted “manually” in /media/overlay by adding the following line mkdir --parents /media/overlay/ && mount -L casper-rw /media/overlay/ to the file rc.local (thank you @sudodus for answering my previous question).

Now, that casper-rw persistance layer is working great… Maybe too great. We would like to erase the /home/<user> directory where the .bash_history and other changes made by the interviewee have been stored when we shut down the test environment (test environment… meaning: the laptop where the interviewee has been doing stuff).

Thanks to these answers (Unix&Linux, AskUbuntu) I created a systemd service that… kindaaaa does what I want, it’s just it seems to do it when the system boots, not when it’s going down. Is not a huge deal, is just… it bugs me a little πŸ˜€

This is the systemd service I created in /etc/systemd/clear-stick.service:

[Unit] Description=Cleans-up interview sticker RequiresMountsFor=/media/overlay/ DefaultDependencies=no Before=shutdown.target reboot.target halt.target umount.target casper.service  [Service] Type=oneshot ExecStart=/usr/local/bin/clear_interview_stick.sh ExecStop=/usr/local/bin/clear_interview_stick.sh RemainAfterExit=true  [Install] WantedBy=multi-user.target 

I suspect it’s only running the ExecStart line on boot, rather than the ExecStop line on shutdown. If I make changes to the /home/ directory, power off the computer and mount the stick somewhere else, the changes are still there. Plus, if I look at the logs in journcalctl I only see references to Cleans-up interview sticker surrounded by what seems start sequences of other services. Yet, I’m not 100% sure whether this happens because the .service definition is wrong (very likely) or because I don’t fully understand how the casper-rw overlay works and eventhough the .service is run on shutdown, it can’t clear the /media/overlay/home/interviewee directory?.

And just in case it’s relevant, this is the content of /usr/local/bin/clear_interview_stick.sh:

#!/bin/bash  had_to_mount="false"; if [[ ! -d "/media/overlay/upper/" ]]; then     mount -L casper-rw /media/overlay/     had_to_mount="true"; fi  if [[ -d "/media/overlay/upper/home/interviewee/" ]]; then     echo "Removing interviewee /home";     rm -rf "/media/overlay/upper/home/interviewee/"; else     echo "interviewee /home/ not found" fi  if [[ -f /root/.bash_history ]]; then     rm /root/.bash_history; fi  if [[ "$  {had_to_mount}" == "true" ]]; then        umount /media/overlay; fi