tcpdump TCP/IP packet sniffer
Sometimes you need a powerful sniffer on your system. Every Mac and every Linux system got it. You just have to use it. tcpdump The only thing you have to…
Clear DNS cache on a Mac
Every Mac caches resolved DNS queries. Sometimes you get entries which create problems. To get rid of them you have to options: reboot the machine. This is the bad one.…
Reset MySQL root password
Sometimes you do not remember a password anymore. Like me just before. I cannot remember the root password of the one MySQL database. Well, that is not really a problem.…
Cisco err-disable recovery
Did it also happen to you, that a port of a remote switch went to err-disable and you had to drive to that location to reset it? Or you have…
Ubuntu do-release-upgrade reconnect
Usually I do a release upgrade over the network, using ssh with the command do-release-upgrade For some reasons the connection to the host I'm upgrading dies. No panic. Reconnect to…
Calculate file checksums using openssl
If you need to calculate the checksum of a file on Mac or UNIX simply use openssl: openssl md5 DeleteCookies.zip openssl sha DeleteCookies.zip This command gives you the checksum of…