Linux, programming and more
While signing a certificate for a new OpenVPN user, I received the following error message which stops the whole process (exit code 1)
Certificate is to be certified until Nov 6 08:53:05 2023 GMT (3650 days)
Sign the certificate? [y/n]:y
failed to update database
TXT_DB error number 2
Problem:
Because you have generated your own self signed certificate with the same CN (Common Name) information that the CA certificate that you’ve generated before.
Enter another Common Name.
Upgrading Fedora from Version Spherical Cow version 18 to the latest Schrödinger’s Cat version 19.
The official Fedora documentation is a good friend.
All following steps as root or with sudo;)
1. Backup your system
2. Do the upgrade
1 2 | yum install fedora-upgrade
fedora-upgrade |
You will be asked at the end for a reboot
After reboot update yum to latest version available in your Fedora version
1 | yum update yum |
3. Clean up
1 | yum clean all |
Enjoy Schrodinger’s Cat
When replacing a failed disk you have to create partitions on the new one. Or simple copy them from the old one.
Clean and prepare new disk:
1 2 | dd if=/dev/zero of=/dev/sdc bs=1024 count=1024 parted --script /dev/sdc mklabel msdos |
Create Partitions overviews from old disk:
1 | sfdisk -d /dev/sda > partitions-sda.txt |
Now read in the crated partition table:
1 | sfdisk /dev/sdc < partitions-sda.txt |
Legend:
old broken disk: /dev/sda
new working one: /dev/sdc
Discard a stock Mailman message from a command line:
1 2 | cd /var/lib/mailman bin/discard data/heldmsg-your-listname-11.pck |
After installing a Solid State Drive in a Windows 7 machine to improve performance in contrast to a normal hard disk drive. I spend some time to find information about the TRIM-support.
A TRIM command allows an operating system to inform a solid-state drive about blocks of data that are no longer considered in use and can be wiped internally.
This technique improves the performance of a ssd drastically.
execute from (CMD) command line with Administrator privileges:
1 | fsutil behavior query DisableDeleteNotify |
DisableDeleteNotify = 0 will mean that TRIM is activated
DisableDeleteNotify = 1 TRIM is deactivated
