¿Cómo poner el conteo de las filas en una consulta en MySql?
SELECT
@rownum := @rownum + 1 AS contador, /*Contador*/
t.* /* nombre de la tabla temporal.campos de la tabla*/
FROM (
SELECT *
FROM `nombretabla`
WHERE `nombretabla`.`campotabla` NOT LIKE "condiciones"
ORDER BY `nombretabla`.`campotabla`
) t, /*nombre de la tabla temporal*/
(SELECT @rownum := 0) r /*incia el contador en cero*/
Tomado de https://stackoverflow.com/questions/1895110/row-number-in-mysql
A LAMP server (Linux + Apache + MariaDB + PHP) allows us to have a web server ready to host sites made with each of the components of the acronym. So, this article will teach you how to install LAMP on Fedora 29 and Fedora 30.
Many web developers use Fedora for their work. It’s not uncommon because we’re talking about a very stable and carefully made Linux distribution. However, it is true that Fedora is not the first choice to install LAMP so many don’t know how to do it.
A LAMP server as I said before is composed of Linux, a web server as Apache, a database manager in MariaDB and a programming language to interpret and make the application work, in this case, PHP. Together, they form an ideal combination to develop web applications and to run applications.
Let’s start.
First, you need to install apache web server. It is perhaps the most used web server in the world. It stands out for its ease of use, its great documentation and its compatibility with almost all Linux distributions. In addition, its installation is quite simple. Let’s get to it.
Open a Terminal and run:
:~# sudo dnf install httpd
Once the installation is complete, you need to start the service and enable it to run at system startup.
:~$ sudo systemctl enable httpd :~$ sudo systemctl start httpd
So far there should be no problems, however, if you want to enable remote access, you have to configure something in the firewall.
:~$ sudo firewall-cmd --permanent --zone=FedoraWorkstation --add-service=http
And finally, restart the Firewall service.
:~$ sudo systemctl restart firewalld
Next, open the web browser and go to localhost. You will see this:
And you can continue with the next step.
PHP is another fundamental component of LAMP. Without it, you will not be able to execute correctly web applications created in this language. So, it is necessary to install it.
:~$ sudo dnf install php php-cli php-xml php-pdo php-mysqlnd php-pear php-mbstring php-mcrypt
Now it is necessary to test the installation. Create a file named example.php in /var/www/html/ with the following content.
:~$ sudo vi /var/www/html/example.php
<?php phpinfo(); ?>
5. Creating a PHP file for testRestart apache service.
:~$ sudo systemctl restart httpd
Open a web browser and open it. http://IP_ADDRESS/example.php and if you see something like this, then everything goes in order.
The next step is to install MariaDB.
Now it’s MariaDB’s turn to install. This is so that the applications that require database can run. MariaDB is a MySQL fork that inherits its strength, robustness, and stability.
:~$ sudo dnf install mariadb mariadb-server
Then, enable the MariaDB service.
:~$ sudo systemctl enable mariadb :~$ sudo systemctl start mariadb
Now, you have to define a password and some extra settings. For this, you will use the MySQL script.
:~$ sudo mysql_secure_installation
To the questions that arise, I have answered: Y, N, Y, Y.
And that’s it.
As you may have noticed, installing LAMP is really easy. The key is to do it methodically and everything becomes easy.
The LAMP is necessary for any web developer and for system administrators to be able to run their web applications.
Please spread this article through your social networks.
Fuente: https://www.osradar.com/how-to-install-lamp-on-fedora-29/
El artículo original está en: https://www.thegeekdiary.com/how-to-delete-disk-partition-using-parted-command/
Before removing the partition, make sure to unmount any partitions on the device and turn off any swap space on the device. Do not remove a partition on a device that is in use. Also take backup of the mount point using that partition, if the data is important to you.
1. Execute parted command to start
# parted
2. Suppose, /dev/sda is the device on which to remove the partition. Use the parted commnad with the /dev/sda device as shown below:
# parted /dev/sda
3. View partition table to determine the minor number of the partition to remove:
4. Remove the partition with the command rm. For example, to remove the partition with minor number 2:
# rm 2
5. After the partition has been removed, use print command to confirm that it is removed from the partition table. You cam view the output of /proc/partitions to make sure the kernel knows the partition has been removed.
# cat /proc/partitions
6. Remove entry from the /etc/fstab file. Find the line that declares the removed partition, and remove it from the file.
# vi /etc/fstab
El artículo original está en: https://www.thegeekdiary.com/how-to-delete-disk-partition-using-parted-command/
El artículo original está en: https://rm-rf.es/gestion-de-particiones-con-parted-en-linux/
Hace un tiempo aprendimos a gestionar discos y particiones con fdisk, ahora vamos ver como trabajar con el programa GNU parted,
que permite particionar y redimensionar discos, así como crear,
redimensionar y copiar sistemas de fichero extX, swap, FAT y FAT32
(luego veremos que es recomendable utilizar las herramientas propias de
Linux en lugar que las que ofrece parted en algunos casos).
Vamos a partir de un disco (virtual) sin particionar. Lo primero que vemos al acceder a parted es un error, ya que parted necesita que el disco tenga una etiqueta (LABEL) para poder trabajar con él:
# parted /dev/sdb GNU Parted 2.1 Usando /dev/sdb Welcome to GNU Parted! Type 'help' to view a list of commands. (parted) print Error: /dev/sdb: unrecognised disk label
Normalmente se utiliza la etiqueta ‘msdos’ ya que Microsoft y OS/2 es la que reconocen, así que la asignamos con el comando mklabel:
(parted) mklabel ¿Nuevo tipo de etiqueta de disco? msdos
En todo momento podéis ver los comandos disponibles escribiendo el signo de interrogación (?)
(parted) ? align-check TYPE N check partition N for TYPE(min|opt) alignment check NUMBER do a simple check on the file system cp [DESDE-DISPOSITIVO] DE-NUMERO A-NUMERO copia el sistema de ficheros a otra partición help [COMMAND] print general help, or help on COMMAND mklabel,mktable LABEL-TYPE create a new disklabel (partition table) mkfs NUMBER FS-TYPE make a FS-TYPE file system on partition NUMBER mkpart TIPO-PART [TIPO-SF] INICIO FIN crea una partición mkpartfs TIPO-PART TIPO-SF INICIO FIN crear una partición con un sistema de ficheros ... ... ...
El comando print nos permite por un lado mostrar todos los dispositivos (discos duros) reconocidos por el sistema:
(parted) print devices /dev/sdb (268MB) /dev/sda (12,7GB)
También las particiones de cada uno y/o el espacio libre:
(parted) print free
Model: ATA VBOX HARDDISK (scsi)
Disk /dev/sdb: 268MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Numero Inicio Fin Tamaño Typo Sistema de ficheros Banderas
32,3kB 268MB 268MB Free Space
Parted nos da la opción de crear una partición y al mismo tiempo el sistema de ficheros (lo vemos más adelante), pero de momento únicamente vamos a crear una partición estándar sin asignar filesystem. Podemos hacer dos cosas, o seguir el asistente o escribir la línea de comandos completa directamente. Para comenzar lo más sencillo es el asistente:
Partición primaria de 100MB que será usada como filesystem ext4
(parted) mkpart ¿Tipo de partición? primary/primaria/extended/extendida? primary ¿Tipo de sistema de ficheros? [ext2]? ext4 ¿Inicio? 1 ¿Fin? 100
Si ejecutamos un print list veremos la nueva partición lista para ser formateada con mkfs.ext4:
(parted) print Model: ATA VBOX HARDDISK (scsi) Disk /dev/sdb: 268MB Sector size (logical/physical): 512B/512B Partition Table: msdos Numero Inicio Fin Tamaño Typo Sistema de ficheros Banderas 1 1049kB 99,6MB 98,6MB primary
Como comentaba antes, parted permite dar formato a la partición en el proceso de creación, aunque claramente vemos al ejecutarlo que recomiendan encarecidamente hacer uso de las herramientas adecuadas para ello (mkfs.extX, e2fsprogs). Así que simplemente vamos a ver como hacerlo por curiosidad (además no soporta ni ext3 ni ext4, sólo ext2…):
WARNING: you are attempting to use parted to operate on (mkpartfs) a file system.
parted’s file system manipulation code is not as robust as what you’ll find in
dedicated, file-system-specific packages like e2fsprogs. We recommend
you use parted only to manipulate partition tables, whenever possible.
Support for performing most operations on most types of file systems
will be removed in an upcoming release.
(parted) mkpartfs WARNING: you are att..... will be removed in an upcoming release. ¿Tipo de partición? primary/primaria/extended/extendida? primary ¿Tipo de sistema de ficheros? [ext2]? ext2 ¿Inicio? 100 ¿Fin? 200
Y ya tenemos la partición con sistema de ficheros ext2:
(parted) print Model: ATA VBOX HARDDISK (scsi) Disk /dev/sdb: 268MB Sector size (logical/physical): 512B/512B Partition Table: msdos Numero Inicio Fin Tamaño Typo Sistema de ficheros Banderas 1 1049kB 99,6MB 98,6MB primary 2 99,6MB 200MB 101MB primary ext2
# mount /dev/sdb2 /test # df -h | grep /test /dev/sdb2 90M 13K 86M 1% /test # umount /test
Para eliminar una partición con parted es tan simple como ejecutar «rm» seguido del número de la partición:
(parted) print Model: ATA VBOX HARDDISK (scsi) Disk /dev/sdb: 268MB Sector size (logical/physical): 512B/512B Partition Table: msdos Numero Inicio Fin Tamaño Typo Sistema de ficheros Banderas 1 1049kB 99,6MB 98,6MB primary 2 99,6MB 200MB 101MB primary ext2
(parted) rm 2 /pre>
Existen otras opciones, como por ejemplo hacer un check al sistema de ficheros, pero igual que con mkpartfs recomiendan utilizar herramientas propias del sistema como fsck. Además, no soportan sistemas de ficheros ext4 o ext3:
(parted) check 1 WARNING: you are attempting to use parted to operate on (check) a file system. parted's file system manipulation code is not as robust as what you'll find in dedicated, file-system-specific packages like e2fsprogs. We recommend you use parted only to manipulate partition tables, whenever possible. Support for performing most operations on most types of file systems will be removed in an upcoming release. Sin Implementación: El soporte para abrir el sistema de ficheros ext4 aún no está implementado.
Si revisáis la página man o la propia salida de ‘?’ veréis otras opciones, como mkfs para formatear sistemas de ficheros (como comentaba antes, no recomendable) y otras más interesantes como rescue, que permite recuperar una partición perdida indicando su posición de inicio y fin:
(parted) rescue INICIO FIN
Os recomiendo como siempre revisar la página man o la salida de ‘?’ para descubrir todas sus posibilidades, como redimensionar una partición con resize, moverla con move, etc. Eso sí, recordad que es preferible usar los comandos/herramientas propios del sistema para mayor seguridad en estos casos.
El artículo original está en: https://rm-rf.es/gestion-de-particiones-con-parted-en-linux/
El artículo original está en: https://www.tecmint.com/create-new-ext4-file-system-partition-in-linux/
The ext4 or fourth extended filesystem is a widely-used journaling file system for Linux. It was designed as a progressive revision of the ext3 file system and overcomes a number of limitations in ext3.
It has significant advantages over its predecessor such as improved design, better performance, reliability, and new features. Although it is best suited for hard drives, it can also be used on removable devices.
This article will show you how to create a new ext4 file system (partition) in Linux. We will first of all look at how to create a new partition in Linux, format it with the ext4 file system and mount it.
Note: For the purpose of this article:
List the partitions using the fdisk -l or parted -l commands to identify the hard drive you want to partition.
# fdisk -l OR # parted -l
Looking at the output in the screenshot above, we have two hard disks added on the test system and we will partition disk /dev/sdb.
Now use parted command to start creating the partition on the selected storage device.
# parted /dev/sdb
Now give the new disk a label using the mklabel command.
(parted) mklabel msdos
Then create a partition using the mkpart command, give it additional parameters like “primary” or “logical” depending on the partition type that you wish to create. Then select ext4 as the file system type, set the start and end to establish the size of the partition:
(parted) mkpart Partition type? primary/extended? primary File system type? [ext2]? ext4 Start? 1 End? 20190
To print the partition table on the device /dev/sdb or detailed information about the new partition, run the print command.
(parted) print
Now exit the program using the quit command.
Next, you need to properly format the new partition with the ext4 file system type using the mkfs.ext4 or mke4fs command as follows.
# mkfs.ext4 /dev/sdb1 OR # mke4fs -t ext4 /dev/sdb1
Then label the partition using the e4label command as follows.
# e4label /dev/sdb1 disk2-part1 OR # e2label /dev/sdb1 disk2-part1
Next, create a mount point and mount the newly created ext4 partition file system.
# mkdir /mnt/disk2-part1 # mount /dev/sdb1 //mnt/disk2-part1
Now using the df command, you can list all file systems on your system together with their sizes in a human readable format (-h), and their mount points and file system types (-T):
# df -hT
Lastly, add the following entry in your /etc/fstab to enable persistent mounting of the file system, even after a reboot.
/dev/sdb1 /mnt/disk2-part1 ext4 defaults 0 0
You might also like to read these following related articles:
That’s all! In this article, we’ve explained how to create a new partition in Linux, format it with ext4 file system type and mount it as a filesystem. For more information or to share any queries with us, use the feedback form below
El artículo original está en: https://www.tecmint.com/create-new-ext4-file-system-partition-in-linux/
Error desconocido. (TAG2 NO (NOPERM) Permission denied (0.001 + 0.000 secs).)
Feb 23 11:51:55 servidor dovecot: imap(usuario): Error: fchown(/home/usuario/mail/.imap/INBOX, group=12(mail)) failed: Operation not permitted (egid=877(usuario), group based on /var/mail/usuario - see http://wiki2.dovecot.org/Errors/ChgrpNoPerm)
Feb 23 11:51:55 servidor dovecot: imap(usuario): Logged out in=32 out=494
Solución
mkdir /home/usuario/mail/.imap/INBOX
My problem is that my Mac starts up to the "El Capitan" installer. After restarting several times, OS X is still on screen telling me that "no packages were eligible for install".
Can someone help please, and can you bear in mind that I’m not technically minded so keep instruction in simple terms.
As explained here, OS X 10.11 "El Capitan" fails to install because it is too old (the technical reason being that the signing certificate is no longer valid).
Como se explica aquí, OS X 10.11 "El Capitán" no se instala porque es demasiado antiguo (la razón técnica es que el certificado de firma ya no es válido).
But you can trick the OS X installer into thinking that it is 2017 and it will happily run without any errors.
Pero puede engañar al instalador de OS X para que piense que es 2017 y se ejecutará felizmente sin errores.
When the OS X installer complains that "No packages were eligible for install" and displays this window: Cuando el instalador de OS X se queja de que "No hay paquetes elegibles para instalar" y muestra esta ventana:
don't restart your Mac. no reinicie su Mac.
Turn Wi-Fi off or unplug the Ethernet cord, depending on your configuration, to prevent your Mac from connecting to the Internet: Apague Wi-Fi o desconecte el cable Ethernet, según su configuración, para evitar que su Mac se conecte a Internet:
Select Utilities>Terminal: Seleccione Utilidades>Terminal:
Click the window that appears: Haga clic en la ventana que aparece:
and type date 0115124517 (this will reset the date to Jan 1st 12:45 2017). After typing the command, press Enter: y escriba la fecha 0115124517 (esto restablecerá la fecha al 1 de enero a las 12:45 de 2017). Después de escribir el comando, presione Enter:
Terminal will confirm that the date has been changed with a line of output that displays the new date. La terminal confirmará que la fecha se ha cambiado con una línea de salida que muestra la nueva fecha.
Quit Terminal: Salga de Terminal:
In the OS X installer window, press Restart: En la ventana del instalador de OS X, presione Reiniciar:
When your Mac comes back up, disable Wi-Fi and leave the Ethernet cord unplugged, as explained in step 2, and press Continue: Cuando su Mac vuelva a funcionar, deshabilite el Wi-Fi y deje el cable Ethernet desconectado, como se explica en el paso 2, y presione Continuar:
Read the software license agreement, press Agree to accept it and press Continue: Lea el acuerdo de licencia de software, presione Aceptar para aceptarlo y presione Continuar:
Select the disk on which you want to install "El Capitan" and press Continue (note that the icon and name of the disk will be different in your case) (there is usually only one option. If you have several options because the Time Machine drive is plugged in to your computer, make sure you select the correct drive and not the Time Machine drive): Seleccione el disco en el que desea instalar "El Capitan" y presione Continuar (tenga en cuenta que el ícono y el nombre del disco serán diferente en su caso) (generalmente solo hay una opción. Si tiene varias opciones porque la unidad Time Machine está conectada a su computadora, asegúrese de seleccionar la unidad correcta y no la unidad Time Machine):
The installation should now proceed without any errors: La instalación ahora debería continuar sin ningún error:
If after you set the date , the WiFi keeps automatically connecting and resetting the date to current date: Si después de configurar la fecha, el WiFi sigue conectándose automáticamente y restableciendo la fecha a la fecha actual:
Turn on WiFi then connect to 'Other' Network. Choose a any network and put in wrong password on purpose. It can't automatically reconnect to WiFi then period. Encienda WiFi y luego conéctese a ' Otra red. Elija cualquier red e ingrese una contraseña incorrecta a propósito. No puede volver a conectarse automáticamente a WiFi y punto.
Now open the terminal, set the date and reboot. When it boots back in it WiFi will be off. Ahora abra la terminal, configure la fecha y reinicie. Cuando se reinicie, WiFi estará apagado.
Follow the screens and setup will then go through normally. Siga las pantallas y la configuración se realizará normalmente.
https://apple.stackexchange.com/questions/394259/mac-stuck-in-el-capitan-installer-loop-no-packages-were-eligible-for-install/394758
date 0102030417(bit easier to type), so that the package installation doesn't fail (that's when it says 24 minutes remaining (Macbook5,1)).