Unix file systems like ext3/4 can store files which are partly empty more efficiently by not storing blocks with all zeros. These files are called sparse files. When reading these files every things works as normal but “all zero” blocks don’t wast space on the drive. This can be useful for different application. For example […]
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Problem: Some flac players refuse to play some flac files, and even tools like an old ffmpeg can’t handle some flac files Solution: These flac files might have id3v2 tags which they realy should not, because flac uses vorbis style tags and not id3. Remove those id3v2 tags with this command: This removes the id3v2
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If you like to block network access for certain users on a linux box it’s as simple as that: /sbin/iptables -I OUTPUT -m owner –uid-ower <USERNAME> -j DROP Username might also be the username of a running service.
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Problem: when debian goes from “testing” to “stable” to “oldstable” the package sources change. eg. jessie-updates are remove, same happened to jessie-backports The current file /etc/apt/sources.list for jessie (currently oldstable) could look like this deb http://ftp.debian.org/debian/ jessie main contrib non-freedeb http://security.debian.org/ jessie/updates main contrib non-free
If you want to configure WLAN settings on a Linux machine statically you can use the normal /etc/network/interfaces configuration method of Debian. For WPA-PSK you can use this 3 steps: Install the “wpasupplicant” package Generate a psk line with “wpa_passphrase” and copy the hex string after “psk=” root@server:~# wpa_passphrase WLANNAME# reading passphrase from stdinthepasswordnetwork={ ssid=”WLANNAME”
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Problem: Mikrotik allows only one ipsec policy per network-to-network pair. If you want to have redundant tunnels between two locations with two upstreams you cannot configure ipsec redundancy on Mikrotik because one ipsec policy is always marked as “invalid” by the OS. Solution: I made a Mikrotik script that checks the status and reachabilty of
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Problem: After upgrading a system to NVME, Linux boots without textconsole, or sends the text console to the wrong graphics card. Discussion: The NVME upgrade needed to change from BIOS boot to UEFI boot. UEFI boot disables the pure text console, and the kernel uses whatever frame buffer is available, or without text console if
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I bought a new notebook, and installed a minimal Linux distribution on it. While setting everything up, I put together a collection of configuration files and scripts, and compiled them in this github repository: https://github.com/alexte/mate-book-pro-x-linux-config
Huawei Mate Book Pro X Read More »
The new Vim 8 on Debian tries again to appeal to the 95% of the people (the noobs) and adds features the are annoying to professionals. When these new features are buggy it’s even worse. Problem: vim 8 on debian 9 has some annoying default settings for vim paste uses a vim internal clipboard instead the
New Vim 8 on Debian 9 Stretch has buggy Mouse/Paste/Syntax handling Read More »
Problem: if you separate the management from the normal traffic on a switch you will usually configure the swtich via this mgmt vpn-instance and also backup and restore config files via this mgmt vpn-instance. But if you use the “backup startup-configuration to ..” it always tries to find the tftp server on the normal network Even after changing
FlexFabric 5700 Backup Config to TFTP in MGMT VPN-Instance Read More »