Archive for the tag 'prompt'

SBDavid

GRUB 2 boot prompt

GRUB 2 boot prompt

If improperly configured, GRUB 2 may fail to load and subsequently drop to a boot prompt. To address this issue, proceed as follows:

1. List the drives which GRUB 2 sees:

grub2> ls

2. The output for a dos partition table /dev/sda with three partitons will look something like this:

(hd0) (hd0,msdos3) (hd0,msdos2) (hd0,msdos1)

3. While the output for a gpt partition table /dev/sda with four partitions will look something like this:

(hd0) (hd0,gpt4) (hd0,gpt3) (hd0,gpt2) (hd0,gpt1)

4. With this information you can now probe each partition of the drive and locate your vmlinuz and initramfs files:

ls (hd0,1)/

Will list the files on /dev/sda1. If this partition contains /boot, the output will show the full name of vmlinuz and initramfs.

5. Armed with the location and full name of vmlinuz and initramfs you can now boot your system.

Creating and editing users in MySQL from shell prompt.

First we need to login into MySQL server as root.

mysql -u root -p

Will be prompted for your MySQL root password (note this is not the same as the server root password).

mysql> create user ‘buddy@localhost’ identified by ‘new-password’;
Query OK, 0 rows affected (0.12 sec)

Next we need to flush the privileges which reloads the ‘user’ table in MySQL - do this each time you add or edit users.

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

To give the user buddy select permission on all the databases, this allows the user to read, but not edit and delete.

mysql> grant select on *.* to ‘buddy’@'localhost’;
Query OK, 0 rows affected (0.00 sec)

The GRANT statement enables system administrators to create MySQL user accounts and to grant rights to accounts. To use GRANT, you must have the GRANT OPTION privilege, and you must have the privileges that you are granting. The REVOKE statement is related and enables administrators to remove account privileges.