Kafka Consumer Error – AVRO with Field Type as a Union of null and boolean

Recently I ran into some issues in consuming Kafka AVRO messages. Everything went well up to the de-serialization of the record from the Kafka topic. It all just went crazy once it was being serialized into JSON. That’s pretty much where the proverbial buck stopped.

I was scratching my head on why this odd behavior was happening. Looking at the message published on the Kafka topic, it was following the defined AVRO schema as expected. There were no deviations.

Somehow when being converted to JSON it started throwing an exception. It was always at the same spot every time. It would not go any further.

Debugging the flow of the program, it showed me that what should have been this:

{
	"fieldOne": "hello world",
	"fieldTwo": true,
	"foobar": false
}

Became something like this:

{
	"fieldOne": "hello world",
	"fieldTwo": true,
	"foobar": {
		"boolean": false
	}
}

And that is why the program was throwing an error!

ANSWER

The solution I did was to remove null as a field type. Set the field to be strictly boolean. What I wanted was to initially have the state of this field as null. Then further down the line it can be set to either true or false.

After the AVRO schema was updated, the error went away.

This was reported to Apache AVRO Jira. More details about this problem here – https://www.joseyamut.xyz/2020/07/29/de-serializing-kafka-messages-with-union-defined-field/

ubunutu server 18 network problem

im new to ubuntu server
i just installed ubuntu server with apache and webmin/virtualmin , i use “CDN provider” to manage my DNS records after i reboot my server i get following error :

/lib/systemd/system-generators/netplan failed with exit status 1
found ordering cycle on network-pre.target/start
found dependency on firewalld.service/stop
found dependency on basic.target/start
found dependency on paths.target/start
found dependency on acpid.path/start

i googled my problem i think i should change setting in netplan config yaml file
but i dont know what should i change ?

Go to Source
Author: user3636770

FTP Issue Proftdp

Trying to install proftpd onto my linux server. It’s showing in the log files successful connection however my client directftp is showing errors.

Here is some info

user1@ily:~$ systemctl status proftpd
● proftpd.service – LSB: Starts ProFTPD daemon
Loaded: loaded (/etc/init.d/proftpd; generated)
Active: active (running) since Sun 2020-06-14 00:07:24 AEST; 15h ago
Docs: man:systemd-sysv-generator(8)
Process: 24178 ExecStop=/etc/init.d/proftpd stop (code=exited, status=0/SUCCES
Process: 24187 ExecStart=/etc/init.d/proftpd start (code=exited, status=0/SUCC
Tasks: 1 (limit: 4915)
CGroup: /system.slice/proftpd.service
└─24211 proftpd: (accepting connections)

Jun 14 00:07:24 ily systemd[1]: Starting LSB: Starts ProFTPD daemon…
Jun 14 00:07:24 ily proftpd[24187]: * Starting ftp server proftpd
Jun 14 00:07:24 ily proftpd[24187]: …done.
Jun 14 00:07:24 ily systemd[1]: Started LSB: Starts ProFTPD daemon.
Jun 14 15:52:46 ily proftpd[30241]: pam_unix(proftpd:session): session opened fo
Jun 14 15:54:56 ily proftpd[30241]: pam_unix(proftpd:session): session closed fo
lines 1-16/16 (END)…skipping…
● proftpd.service – LSB: Starts ProFTPD daemon
Loaded: loaded (/etc/init.d/proftpd; generated)
Active: active (running) since Sun 2020-06-14 00:07:24 AEST; 15h ago
Docs: man:systemd-sysv-generator(8)
Process: 24178 ExecStop=/etc/init.d/proftpd stop (code=exited, status=0/SUCCESS)
Process: 24187 ExecStart=/etc/init.d/proftpd start (code=exited, status=0/SUCCESS)
Tasks: 1 (limit: 4915)
CGroup: /system.slice/proftpd.service
└─24211 proftpd: (accepting connections)

Jun 14 00:07:24 ily systemd[1]: Starting LSB: Starts ProFTPD daemon…
Jun 14 00:07:24 ily proftpd[24187]: * Starting ftp server proftpd
Jun 14 00:07:24 ily proftpd[24187]: …done.
Jun 14 00:07:24 ily systemd[1]: Started LSB: Starts ProFTPD daemon.
Jun 14 15:52:46 ily proftpd[30241]: pam_unix(proftpd:session): session opened for user proftpd by (uid=0)
Jun 14 15:54:56 ily proftpd[30241]: pam_unix(proftpd:session): session closed for user proftpd

Go to Source
Author: zeusloveunited

How can I get multipathd to stop monitoring my disk?

I’m booting Ubuntu server 20.04 from a single nvme disk.
Since a couple of days ago, multipath has been spamming my syslog with these messages:

Jun 11 20:10:14 xb multipath: nvme0n1: failed to get udev uid: Invalid argument
Jun 11 20:10:14 xb multipath: nvme0n1: uid = eui.0000000001000000e4d25c7f117c5001 (sysfs)
Jun 11 20:10:17 xb multipath: nvme0n1: failed to get udev uid: Invalid argument
Jun 11 20:10:17 xb multipath: nvme0n1: uid = eui.0000000001000000e4d25c7f117c5001 (sysfs)
Jun 11 20:10:20 xb multipath: nvme0n1: failed to get udev uid: Invalid argument
Jun 11 20:10:20 xb multipath: nvme0n1: uid = eui.0000000001000000e4d25c7f117c5001 (sysfs)
Jun 11 20:11:34 xb multipath: nvme0n1: failed to get udev uid: Invalid argument
Jun 11 20:11:34 xb multipath: nvme0n1: uid = eui.0000000001000000e4d25c7f117c5001 (sysfs)
Jun 11 20:11:37 xb multipath: nvme0n1: failed to get udev uid: Invalid argument
Jun 11 20:11:37 xb multipath: nvme0n1: uid = eui.0000000001000000e4d25c7f117c5001 (sysfs)

I can get the following list of devices to confirm it monitors my nvme disk:

multipathd> show devices
available block devices:
loop1 devnode blacklisted, unmonitored
nvme0n1 devnode whitelisted, monitored
loop6 devnode blacklisted, unmonitored
loop4 devnode blacklisted, unmonitored
loop2 devnode blacklisted, unmonitored
loop0 devnode blacklisted, unmonitored
loop7 devnode blacklisted, unmonitored
loop5 devnode blacklisted, unmonitored
loop3 devnode blacklisted, unmonitored
multipathd> 

I tried the command:

remove map nvme0n1

But got the message: fail

So now the question is, how can I get it to stop monitoring my nvme disk and spamming the syslog?

Go to Source
Author: Artur Meinild

what is Showbox for PC

The ShowBox is a famous 3rd party media streaming and downloading app for Android. It’s presently not available to download directly from the Google Play Store. To download and install Showbox on your Android smartphone, you’ll need to modify a few settings on your device. You can also use Showbox for PC

Go to Source
Author: showbox98