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After researching 42 wireless mice and testing 14, we found that the Logitech M720 Triathlon Multi-Device Wireless Mouse is the best wireless mouse for most people because it is more comfortable to use than nearly every other mouse we tested, connects easily via a USB dongle or Bluetooth, and tracks well on most surfaces.
via Wirecutter: Reviews for the Real World
The Best Wireless Mouse
You’re trying to save data on your USB flash storage, but there’s a problem. Any attempt to save displays the message that the drive is “write protected”. How can this be?
The drive won’t even allow you to reformat it, and there’s no apparent switch for enabling or disabling write protection. Puzzled? Here’s how to format your write protected USB flash drive and start using it again.
Before proceeding, take the time to make sure that the drive is genuinely write protected. A couple of other issues could be coming into play here.
Confident the problem is just write protection on your USB flash stick? Let’s move on.
Before starting, insert your USB flash drive into your computer’s USB port.
Windows has a built-in disk partition management tool called Diskpart. You can open this by hitting Windows key + R, entering cmd, then hitting Enter.
User Access Control will prompt you to confirm the action. Click Yes to continue.
You should now see CMD, the command line tool. At the prompt, enter
diskpartA new command line window will open, with a new DISKPART prompt. It’s time to see which disks are attached to your computer:
list diskThe resulting table will list the currently available devices. But which is your USB drive?
Disk 0 will be your computer’s system drive. This is the one that Windows is installed on. If you have multiple partitions, these will be sequentially numbered. Note that the size is displayed for each disk.
With a USB flash device connected, (which will be Disk 1 or higher) you should be able to identify it by its comparatively low capacity.
In the image above, while Disk 0 is 119GB and Disk 1 931GB (two partitions of the same drive), Disk 2 is 16GB.
Therefore, Disk 2 is the USB flash drive. You should be able to check the capacity on the device itself, as this is usually printed on a drive’s casing. If not, you’ll be able to confirm it in Windows Explorer.
Before proceeding further, be absolutely certain that you have identified the USB flash drive. Note also that USB flash drives can be as high as 1TB in capacity (like the PNY Pro Elite) at the time of writing, which could be larger than your computer’s HDD. Making the effort to be totally certain at this stage is vital to the integrity of the data on your computer!
PNY Pro Elite 1TB USB Flash Drive
PNY Pro Elite 1TB USB Flash Drive
via MakeUseOf.com
How to Format a Write Protected USB Flash Drive
by Dennis Crouch
I first worked with Wes Austin back in 2006 as he developed his Dunes CLE program and later followed with some interest his Utah-based patent firm Austin-Rapp. As the image shows below, Austin has expanded from patent law into comedy as well. His new sitcom – THE IP SECTION – merges the two (as well as Mormonism) and stars a patent lawyer who wants to be a stand-up comedian.
Watch the series here:
Do any of your experiences as a patent attorney or inventor fit easily into a comedy routine?
via Patent Law Blog (Patently-O)
The IP Section — Stream the First Four Episodes
The Firearm Blog has partnered with Lone Wolf Distributors to bring you a series on building your own Glock. Buying an 80% receiver is not new to the gun industry. Glocks are the rage, why not build one the way YOU want it? Get yourself a hot gat, and loose that Fudd factory gun. Get that sweet trigger in there, and pay no attention to the factory fanboys. (Factory purest click here)
I looked at my Gen 2 Glock 21 and figured she is probably ready to retire to safe queen status, therefore, clearly time for my next Glock. I already own a (cough) number of Glocks, but I decided this has to be a hot gat. Rather than paying top dollar for a pimped out Glock, I want to build exactly what I want the way I want.
Taking an 80% receiver is perfectly legal, and surprisingly common. I know of a retired military operator who has built a half dozen and working on another. In this series, I will be building my pimped out Glock 19. RMR ready and eventually suppressed.
So dear reader hit that link below, visit Lone Wolf, get yourself an 80% receiver and join us for this surprisingly easy adventure in building yourself a Glock. If it is for a Glock, these guys have it.
Everything you will ever need for your Glock. Check them out.
The 80% frame will arrive in the jig you will use to remove the material to bring the frame to 100%. It also ships with the drill bits required. I will go over all of this in the series, step by step.
Next addition I will briefly address the legality, as I sat down with an ATF agent before I started. A very cool guy who helped me out with pitfalls people run into. Then I will start creating my new sweet non-factory Glock.
I know there a lot of you who have already built up an 80% frame. What do you think? How was your experience? Let us know below
Lone Wolf THE leading Glock accessory supplier – (Click here)
We are committed to finding, researching, and recommending the best products. We earn commissions from purchases you make using the retail links in our product reviews.
Learn more about how this works
.
In this blog we will investigate why and how to solve these problems when running MySQL installed on Debian/Ubuntu using systemd (default MySQL packages).
OS: Debian 9
MySQL Server version: 5.7.25 MySQL Community Server (GPL)
(will most likely be the same for MySQL 8.0 versions)
Goal is to have 10.000 working connections to MySQL!
The default value for max_connections is 151 connections so first step is to increase the max_connections variable to 10.000.
This is documented in the manuals here:
– https://ift.tt/23yLjHw
– https://ift.tt/2FNe7om
The max_connections is a dynamic setting so lets increase value to 10.000 and see what happens.
|
root@debian:~# mysql -uroot -proot -se "select @@max_connections" @@max_connections 214 |
Hmmm, it looks like we only got 214 connections, lets look at the error log:
|
2019-04-01T06:29:48.301871Z 0 [Warning] Changed limits: max_open_files: 1024 (requested 50000) 2019-04-01T06:29:48.302000Z 0 [Warning] Changed limits: max_connections: 214 (requested 10000) 2019-04-01T06:29:48.302004Z 0 [Warning] Changed limits: table_open_cache: 400 (requested 2000) |
Looks like we hit some resource limit.
Lets look in the MySQL manual for running MySQL under systemd, that can be found here.
Looks like we need to increase the number of allowed open files for MySQL, locate the systemd configuration file for MySQL and create the /etc/systemd/system/mysqld.service.d/override.conf (file can be called anything ending with .conf).
Add LimitNOFILE=10000 in file override.conf like:
|
root@debian:~# cat /etc/systemd/system/mysql.service.d/override.conf [Service] LimitNOFILE=10000 |
After this we need to reload the systmed daemon and restart the MySQL service like:
|
root@debian:~# systemctl daemon-reload root@debian:~# systemctl restart mysql |
MySQL is now saying we have 9190 connections:
|
root@debian:~# mysql -uroot -proot -se "select @@max_connections" @@max_connections 9190 |
So, MySQL is using some files for additional work and we need to set this a bit higher to get 10.000 connections, lets set it to 11.000 and reload the systemd daemon and restart the MySQL service.
|
root@debian:~# mysql -uroot -proot -se "select @@max_connections" mysql: [Warning] Using a password on the command line interface can be insecure. @@max_connections 10000 |
Good, now we have 10.000 connections available according to MySQL.
Lets run our application and verify we can get 10.000 connections, I use this small perl script to open 10.000 connections.
Just below 5.000 connection I get a new error in the application "Can’t create a new thread (errno 11)"
Lets have a look at the MySQL error log:
|
root@debian:~# tail -1 /var/log/mysql/error.log 2019-04-01T06:50:35.657397Z 0 [ERROR] Can’t create thread to handle new connection(errno= 11) |
I found this new limit by running command below when perl script was running:
watch -n.5 "mysql -uroot -proot -se’show status like \"%threads%\"’"
Strange, where is this new limitation just below 5.000 connections coming from?
Looking at resource limits for my MySQL daemon I should have close to 8000 processes:
|
root@debian:~# cat /proc/$( pgrep -o mysql )/limits Max processes 7929 7929 processes Max open files 11000 11000 files |
Lets looks at status report for my MySQL service:
|
root@debian:~# systemctl status mysql | grep Tasks Tasks: 127 (limit: 4915) |
There seem to be some additional limit on Tasks that limit me to 4915 connections.
Lets expand our override.conf configuration to cover for 11.000 tasks also.
|
root@debian:~# cat /etc/systemd/system/mysql.service.d/ [Service] LimitNOFILE=11000 TasksMax=11000 |
(remember to reload systemd and restart MySQL service after each change in override.conf)
Now we got just under 8.000 connection and got the same error " Can’t create a new thread (errno 11)" but this time it’s because of the limit of max processes:
|
root@debian:~# cat /proc/$( pgrep -o mysql )/limits Max processes 7929 7929 processes |
Lets increase this limit to 11000 in our override.conf:
|
root@debian:~# cat /etc/systemd/system/mysql.service.d/override.conf and [Service] LimitNOFILE=11000 LimitNPROC=11000 TasksMax=11000 |
After reloading systemd configuration and restarting MySQL service I can now get
10.000 connections and the perl script runs without any errors!
Summary:
There are different limits when setting max_connections in MySQL:
– The default max connections is 151.
– At 214 connections you are limited by max open files.
– At 4915 you are limited by Max Tasks (systemd)
– Just below 8000 you are limited by max number of processes
By adding a override file (as showed above) you can overcome all these limits.
Remember to:
Look at error message in application and MySQL error logs.
Look at output from: cat /proc/$( pgrep -o mysql )/limits
Look at output from: systemctl status mysql
Test your application (or use my perl script) and monitor that it works!
Monitor how many connections you have: watch -n.5 "mysql -uroot -proot -se’show status like \"Threads_connected\"’"
Best Gaming DealsThe best deals on games, consoles, and gaming accessories from around the web, updated daily. Right now, Twitch Prime subscribers can get up to a year of Nintendo Switch Online benefits, including online play, access to classic NES games, and other benefits thanks to Twitch Prime.
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via Gizmodo
Got Amazon Prime? You Can Get a Free Year of Nintendo Switch Online.
MailEclipse is a mailable editor package for your Laravel applications to create and manage mailables using a web UI. You can use this package to develop mailables without using the command line, and edit templates associated with mailables using a WYSIWYG editor, among other features.
You can even edit your markdown mailable templates:
When creating a mailable template, you can pick from existing themes provided by this package:
The best way to get an idea of what this package does is to install it and try it out or check out this five-minute demo from the author:
Note: the video doesn’t provide sound, but does give an excellent overview and demo of MailEclipse features.
At the time of writing this package is a work in progress and under active development. Part of being under active development means that if you’re interested, you’re encouraged to try this package out and provide feedback.
To start using this package, check out the source code and readme at Qoraiche/laravel-mail-editor on GitHub.
Filed in: News
No Spam, ever. We’ll never share your email address and you can opt out at any time.
Move the Slow log to a table
mysql> select count(*) from mysql.slow_log;
+----------+
| count(*) |
+----------+
| 0 |
+----------+
1 row in set (0.00 sec)
mysql> select @@slow_query_log,@@sql_log_off;
+------------------+---------------+
| @@slow_query_log | @@sql_log_off |
+------------------+---------------+
| 1 | 0 |
+------------------+---------------+
mysql> set GLOBAL slow_query_log=0;
Query OK, 0 rows affected (0.04 sec)
mysql> set GLOBAL sql_log_off=1;
Query OK, 0 rows affected (0.00 sec)
mysql> ALTER TABLE mysql.slow_log ENGINE = MyISAM;
Query OK, 0 rows affected (0.39 sec)
mysql> set GLOBAL slow_query_log=0;
Query OK, 0 rows affected (0.04 sec)
mysql> set GLOBAL sql_log_off=1;
Query OK, 0 rows affected (0.00 sec)
mysql> ALTER TABLE mysql.slow_log ENGINE = MyISAM;
Query OK, 0 rows affected (0.39 sec)
mysql> set GLOBAL slow_query_log=1;
Query OK, 0 rows affected (0.00 sec)
mysql> set GLOBAL sql_log_off=0;
Query OK, 0 rows affected (0.00 sec)
mysql> SET GLOBAL log_output = 'TABLE';
Query OK, 0 rows affected (0.00 sec)
mysql> SET GLOBAL log_queries_not_using_indexes=0;
Query OK, 0 rows affected (0.00 sec)
mysql> select count(*) from mysql.slow_log;
+----------+
| count(*) |
+----------+
| 0 |
+----------+
1 row in set (0.00 sec)
mysql> select @@slow_launch_time;
+--------------------+
| @@slow_launch_time |
+--------------------+
| 2 |
+--------------------+
1 row in set (0.00 sec)
mysql> SELECT SLEEP(10);
+-----------+
| SLEEP(10) |
+-----------+
| 0 |
+-----------+
1 row in set (9.97 sec)
mysql> select count(*) from mysql.slow_log;
+----------+
| count(*) |
+----------+
| 1 |
+----------+
1 row in set (0.00 sec)
mysql> select * from mysql.slow_log\G
*************************** 1. row ***************************
start_time: 2019-03-27 18:02:32
user_host: klarson[klarson] @ localhost []
query_time: 00:00:10
lock_time: 00:00:00
rows_sent: 1
rows_examined: 0
db:
last_insert_id: 0
insert_id: 0
server_id: 502
sql_text: SELECT SLEEP(10)
thread_id: 16586457
Now you can truncate it or dump it or whatever you like to do with this data easily also.
Note variable values into your my.cnf file to enable upon restart.
Set report_host_name
report_host = <hostname> <or whatever you want to call it>
mysql> show slave hosts;
+-----------+-------------+------+-----------+--------------------------------------+
| Server_id | Host | Port | Master_id | Slave_UUID |
+-----------+-------------+------+-----------+--------------------------------------+
| 21235302 | <hostname> | 3306 | 21235301| a55faa32-c832-22e8-b6fb-e51f15b76554 |
+———–+————-+——+———–+————————————–+
Set master & slaves to use tables
mysql> show variables like '%repository';
+---------------------------+-------+
| Variable_name | Value |
+---------------------------+-------+
| master_info_repository | FILE |
| relay_log_info_repository | FILE |
+---------------------------+-------+
mysql_slave> stop slave;
mysql_slave> SET GLOBAL master_info_repository = 'TABLE';
mysql_slave> SET GLOBAL relay_log_info_repository = 'TABLE';
mysql_slave> start slave;
Make sure you add to my.cnf to you do not lose binlog and position at a restart. It will default to FILE otherwise.
mysql> show variables like '%repository';
---------------------+-------+
| Variable_name | Value |
+---------------------------+-------+
| master_info_repository | TABLE |
| relay_log_info_repository | TABLE |
+---------------------------+-------+
All data is available in tables now and easily stored with backups
mysql> desc mysql.slave_master_info;
+------------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------------------+---------------------+------+-----+---------+-------+
| Number_of_lines | int(10) unsigned | NO | | NULL | |
| Master_log_name | text | NO | | NULL | |
| Master_log_pos | bigint(20) unsigned | NO | | NULL | |
| Host | char(64) | YES | | NULL | |
| User_name | text | YES | | NULL | |
| User_password | text | YES | | NULL | |
| Port | int(10) unsigned | NO | | NULL | |
| Connect_retry | int(10) unsigned | NO | | NULL | |
| Enabled_ssl | tinyint(1) | NO | | NULL | |
| Ssl_ca | text | YES | | NULL | |
| Ssl_capath | text | YES | | NULL | |
| Ssl_cert | text | YES | | NULL | |
| Ssl_cipher | text | YES | | NULL | |
| Ssl_key | text | YES | | NULL | |
| Ssl_verify_server_cert | tinyint(1) | NO | | NULL | |
| Heartbeat | float | NO | | NULL | |
| Bind | text | YES | | NULL | |
| Ignored_server_ids | text | YES | | NULL | |
| Uuid | text | YES | | NULL | |
| Retry_count | bigint(20) unsigned | NO | | NULL | |
| Ssl_crl | text | YES | | NULL | |
| Ssl_crlpath | text | YES | | NULL | |
| Enabled_auto_position | tinyint(1) | NO | | NULL | |
| Channel_name | char(64) | NO | PRI | NULL | |
| Tls_version | text | YES | | NULL | |
| Public_key_path | text | YES | | NULL | |
| Get_public_key | tinyint(1) | NO | | NULL | |
+------------------------+---------------------+------+-----+---------+-------+
27 rows in set (0.05 sec)
mysql> desc mysql.slave_relay_log_info;
+-------------------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------------------+---------------------+------+-----+---------+-------+
| Number_of_lines | int(10) unsigned | NO | | NULL | |
| Relay_log_name | text | NO | | NULL | |
| Relay_log_pos | bigint(20) unsigned | NO | | NULL | |
| Master_log_name | text | NO | | NULL | |
| Master_log_pos | bigint(20) unsigned | NO | | NULL | |
| Sql_delay | int(11) | NO | | NULL | |
| Number_of_workers | int(10) unsigned | NO | | NULL | |
| Id | int(10) unsigned | NO | | NULL | |
| Channel_name | char(64) | NO | PRI | NULL | |
+-------------------+---------------------+------+-----+---------+-------+
Turn off log_queries_not_using_indexes until needed
mysql> SET GLOBAL log_queries_not_using_indexes=0;
Query OK, 0 rows affected (0.00 sec)
mysql> SET GLOBAL log_queries_not_using_indexes=1;
Query OK, 0 rows affected (0.00 sec)
Note variable values into your my.cnf file to enable upon restart.
Side note — USE ALGORITHM=INPLACE
mysql> ALTER TABLE TABLE_DEMO ALGORITHM=INPLACE, ADD INDEX `datetime`(`datetime`);
Query OK, 0 rows affected (1.49 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> ALTER TABLE TABLE_DEMO ALGORITHM=INPLACE, ADD INDEX `datetime`(`datetime`);
Query OK, 0 rows affected (1.49 sec)
Records: 0 Duplicates: 0 Warnings: 0
Side note — USE mysql_config_editor
mysql_config_editor set --login-path=local --host=localhost --user=root --password
Enter password:
# mysql_config_editor print --all
[local]
user = root
password = *****
host = localhost
# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
# mysql --login-path=local
Welcome to the MySQL monitor.
# mysql --login-path=local -e 'SELECT NOW()';
via Planet MySQL
Every MySQL should have these variables set …
MySQL 8.0 brings a lot of new features. These features make MySQL database much more secure (like new authentication, secure password policies and management, …) and fault tolerant (new data dictionary), more powerful (new redo log design, less contention, extreme scale out of InnoDB, …), better operation management (SQL Roles, instant add columns), many (but really many!) replication enhancements and native group replication… and finally many cool stuff like the new Document Store, the new MySQL Shell and MySQL InnoDB Cluster that you should already know if you follow this blog (see these TOP 10 for features for developers and this TOP 10 for DBAs & OPS).
We saw in this previous post how to migrate from MariaDB 5.5 (default on CentOS/RedHat 7) to MySQL. This was a straight forward migration as at the time MariaDB was a drop in replacement for MySQL…but this is not the case anymore since MariaDB 10.x !
Lets get started with the migration to MySQL 8.0 !
Two possibilities are available to us:
It’s recommended to avoid to have to deal with mysql.* tables are they won’t be compatible, I recommend you to save all that information and import the required entries like users manually. It’s maybe the best time to do some cleanup.
As we are still using our WordPress site to illustrate this migration. I will dump the wp database:
# mysqldump -B wp > wp.sql
MariaDB doesn’t provide
mysqlpump, so I used the good oldmysqldump. There was a nice article this morning about MySQL logical dump solutions, see it here.
First we take a dump of our database without the data (-d):
# mysqldump -d -B wp > wp_nodata.sq
Then we export the first table space:
[wp]> flush tables wp_comments for export;
Query OK, 0 rows affected (0.008 sec
We copy it to the desired location (the .ibd and the .cfg):
# cp wp/wp_comments.ibd ~/wp_innodb/
# cp wp/wp_comments.cfg ~/wp_innodb/
And finally we unlock the table:
[wp]> unlock tables;
These operation above need to be repeated for all the tables ! If you have a large amount of table I encourage you to script all these operations.
Unlike previous version, if we install MySQL from the Community Repo as seen on this post, MySQL 8.0 won’t be seen as a conflicting replacement for MariaDB 10.x. To avoid any conflict and installation failure, we will replace the MariaDB packages by the MySQL ones using the swap command of yum:
# yum swap -- install mysql-community-server mysql-community-libs-compat -- \
remove MariaDB-server MariaDB-client MariaDB-common MariaDB-compat
This new yum command is very useful, and allow other dependencies like php-mysql or postfix for example to stay installed without breaking some dependencies
The result of the command will be something similar to:
Removed:
MariaDB-client.x86_64 0:10.3.13-1.el7.centos
MariaDB-common.x86_64 0:10.3.13-1.el7.centos
MariaDB-compat.x86_64 0:10.3.13-1.el7.centos
MariaDB-server.x86_64 0:10.3.13-1.el7.centos
Installed:
mysql-community-libs-compat.x86_64 0:8.0.15-1.el7
mysql-community-server.x86_64 0:8.0.15-1.el7
Dependency Installed:
mysql-community-client.x86_64 0:8.0.15-1.el7
mysql-community-common.x86_64 0:8.0.15-1.el7
mysql-community-libs.x86_64 0:8.0.15-1.el7
Now the best is to empty the datadir and start mysqld:
# rm -rf /var/lib/mysql/*
# systemctl start mysq
This will start the initialize process and start MySQL.
As you may know, by default MySQL is now more secure and a new password has been generated to the root user. You can find it in the error log (/var/log/mysqld.log):
2019-03-26T12:32:14.475236Z 5 [Note] [MY-010454] [Server]
A temporary password is generated for root@localhost: S/vfafkpD9a
At first login with the root user, the password must be changed:
# mysql -u root -p
mysql> set password='Complicate1#'
Now we need to create our database (wp), our user and its credentials.
Please, note that the PHP version used by default in CentOS might now be yet compatible with the new default secure authentication plugin, therefor we will have to create our user with the older authentication plugin,
mysql_native_password. For more info see these posts:– Migrating to MySQL 8.0 without breaking old application
mysql> create user 'wp'@'127.0.0.1' identified with
'mysql_native_password' by 'fred';
By default, this password (fred) won’t be allowed with the default password policy.
To not have to change our application, it’s possible to override the policy like this:
mysql> set global validate_password.policy=LOW;
mysql> set global validate_password.length=4
It’s possible to see the user and its authentication plugin easily using the following query:
mysql> select Host, User, plugin,authentication_string from mysql.user where User='wp';
+-----------+------+-----------------------+-------------------------------------------+
| Host | User | plugin | authentication_string |
+-----------+------+-----------------------+-------------------------------------------+
| 127.0.0.1 | wp | mysql_native_password | *6C69D17939B2C1D04E17A96F9B29B284832979B7 |
+-----------+------+-----------------------+-------------------------------------------+
We can now create the database and grant the privileges to our user:
mysql> create database wp;
Query OK, 1 row affected (0.00 sec)
mysql> grant all privileges on wp.* to 'wp'@'127.0.0.1';
Query OK, 0 rows affected (0.01 sec)
This process is also defined by the options chosen earlier.
This option, is the most straight forward, one restore and our site is back online:
# mysql -u wp -pfred wp <~/wp.sql
This operation is more complicated as it requires more steps.
First we will have to restore all the schema with no data:
# mysql -u wp -pfred wp <~/wp_nodata.sql
And now for every tables we need to perform the following operations:
mysql> alter table wp_posts discard tablespace;
# cp ~/wp_innodb/wp_posts.ibd /var/lib/mysql/wp/
# cp ~/wp_innodb/wp_posts.cfg /var/lib/mysql/wp/
# chown mysql. /var/lib/mysql/wp/wp_posts.*
mysql> alter table wp_posts import tablespace
Yes, this is required for all tables, this is why I encourage you to script it if you choose this option.
So as you could see, it’s still possible to migrate from MariaDB to MySQL but since 10.x, this is not a drop in replacement anymore and requires several steps including logical backup.
While working on a completely different project I discovered something curious on Amazon. That product was moldable thermoplastic pellets. Shaped in balls like smaller-than-usual airsoft pellets, moldable thermoplastic melts at just 140F, can be formed like clay, and then increases in hardness as it approaches room temperature. There are seemingly endless uses for this product, but I had a pet… more
via Recoil
Make Gun Tools That Don’t Exist with Moldable Thermoplastic