Sometimes it would be useful to print file contents or output of previously executed command in reverse. There are two little utilities that are part of Linux coreutils: tac and rev. TAC concatenates and prints files in reverse (last line first). REV reverses lines of a file: it copies the specified files to the standard output, reversing the order of characters in every line.
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MTR is a tool that combines the Unix/Linux traceroute and ping programs functionality in a single network diagnostic tool. As mtr starts, it investigates the network connection between the host mtr runs on and certain HOSTNAME by sending packets with purposly low TTLs. It continues to send packets with low TTL, noting the response time of the intervening routers. This allows mtr to print the response percentage and response [...]
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Here is list of some useful resources regarding OpenBSD Packet Filter: PF User’s Guide by by Wouter Coene NAT with pf by Jacek Artymiak Securing Small Networks with OpenBSD by Jacek Artymiak Firewalling with PF by Peter N. M. Hansteen (norwegian version, pdf, and slides available, too) A Newbie’s Guide to Setting up PF on OpenBSD by Eric Bullen A Beginner’s Guide To Firewalling with pf Guide to OpenBSD Packet [...]
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Few will deny that applications allowing to create notes at Linux Desktop are very useful to plan one’s working/education process. As for me I use such applications in order not to forget something I want to do like blog posts came to my mind when I hadn’t access to Internet, everyday system administrating tasks and others. I tried several sticky notes applications for this purpose but only one seems to [...]
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There are many ways to transmit files between computers over the heterogeneous network (Linux, Windows, Apple MAC and other systems). I used to run SCP for my every day administrative tasks, especially when client SCP utility is available for Windows too. But here is useful tip on how to transmit files over network with no need to install and configure any service at server: just run at Linux or Unix [...]
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