An old article by Todd Partridge (Gently) but still really useful if you are writing some bash scripts and want them more readable with some colors:
Users who have been using Linux for awhile often learn that creating a basic script is a good way to run multiple, often-repeated commands. Adding a little color to scripts can additionally provide nice feedback. This can be done in a fairly straight-forward way by using the tput command.
Often one wants a shared access to files across machines. Traditionally one uses the network file system (nfs). The network file server works as follows: There is an nfs server that exports some directories in its filesystem hiearchy to various nfs clients that mount these directory over the network into their file system hierarchy. As a result, each of the clients shares the directories exported by the nfs server.
However a lot of times you just have to mount a directory from a server to your local computer and in these cases NFS it’s not so useful, sshfs it’s much better
Sshfs is a filesystem client based on the SSH File Transfer Protocol. Since most SSH servers already support this protocol it is very easy to set up: i.e. on the server side there’s nothing to do. On the client side mounting the filesystem is as easy as logging into the server with ssh.
Article by Rahul Panwar first posted on http://linuxexplore.com/
A chroot on Unix operating systems is an operation that changes the apparent root directory for the current running process and its children. A program that is run in such a modified environment cannot name (and therefore normally not access) files outside the designated directory tree. The term “chroot” may refer to the chroot(2) system call or the chroot(8) wrapper program. The modified environment is called a “chroot jail”. From Wikipedia.
Why it is required? If you want to set up your Linux box as a web hosting server for its users, you may need to give SFTP access. But they can get access to whole system Linux tree, just for reading but still very unsecure. So it is mandatory to lock them in their home directory.
There are many other applications, it’s just a common example, so lets start its configuration.
Sometimes you need to clone partitions on your hard drive for various reasons, hd damaged, creating a RAID 1 or something similar, then it is often tedious and impractical to perform the operation using the normal tools like fdisk, in this case you can use sfdisk.
As reported in the manual:
sfdisk is a non-interactive program to edit the partition table, which is useful for creating scripts. The normal use of this service program involves the preparation of a file containing the instructions on the partitions to be created within a disk specified explicitly. Even if there is a special syntax for these instructions, it may be convenient to use since it is obtained from a query with the same sfdisk, as will be shown.
I use ssh everyday and it’s my main tool to connect and manage servers, so I’m always interested in articles about ssh.
Today I present an interesting article on this subject, written by Corey Quinn and posted on the sysadvent blog
Every year or two, I like to look back over my client’s SSH configuration file and assess what I’ve changed.
This year’s emphasis has been on a few options that center around session persistence. I’ve been spending a lot of time on the road this year, using SSH to log into remote servers over terrible hotel wireless networks. As a result, I’ve found myself plagued by SSH session resets. This can be somewhat distracting when I’m in the midst of a task that requires deep concentration— or in the middle of editing a configuration file without the use of screen or tmux.
ServerAliveInterval 60This triggers a message from the client to the server every sixty seconds requesting a response, in the event that data haven’t been received from the server in that time. This message is sent via SSH’s encrypted channel.