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What does "Error: Cycle". means in Terraform?

The Terraform docs for some weird reason do not explain what "Error: Cycle" means. I've looked everywhere but there is no mention of it on the official docs. (Turns out it is well-known term, a circular dependency, that someone apparently renamed…
Juan Jimenez
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64
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13 answers

Linux: productive sysadmins without root (securing intellectual property)?

Is there any way to make a seasoned Linux syadmin productive without giving him full root access? This question comes from a perspective of protecting intellectual property (IP), which in my case, is entirely code and/or configuration files (i.e.…
Matt
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64
votes
2 answers

When building from Dockerfile, Debian/Ubuntu package install debconf Noninteractive install not allowed

I've set the following environment so that no question/dialog is asked during apt-get install: ENV DEBIAN_FRONTEND noninteractive # export DEBIAN_FRONTEND="noninteractive" Which is equivalent to: export DEBIAN_FRONTEND="noninteractive" Yet,…
Phil L.
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64
votes
7 answers

What's the best way to see logged in users in Windows Server 2012?

Right now I use a powershell script to see the currently logged in users. But I don't see if their session is idle, active or inactive. I can see when the session was started, that's it. Is there an easy way to see how many users are currently…
64
votes
10 answers

How do I check the postfix queue size?

What's the postfix equivalent to sendmail -bp?
Gary Richardson
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64
votes
7 answers

How to change a SSH host key?

I cloned a server and so they've the same RSA key fingerprint. It seems to be defined in /etc/ssh/ssh_host_rsa_key.pub. What is the correct way to change that? Thanks.
Pascal Polleunus
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64
votes
4 answers

Suspicious symbols on nginx config

I have the following nginx config, e.g. server { listen 80; server_name example.com allow 127.0.0.0/8; When I restart, it warn me: Restarting nginx: nginx: [warn] server name "127.0.0.0/8" has suspicious symbols in…
Ryan
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64
votes
11 answers

What can cause slow ssh session?

I ssh on remote host but terminal performance is poor. Symbols I am typing are not shown immediately, but with some delay. Sometimes two symbols are shown at one time after delay.
lexsys
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64
votes
9 answers

Creating a virtual machine in VirtualBox from a physical one

Is there any way to create a virtual machine that you can use in VirtualBox from a physical installation that you have? For instance, if I have Windows XP installed on a physical computer and want to have a virtual version of that machine on a…
64
votes
2 answers

Executing a command as a nologin user

I've recently set up my server so that my suPHP 'virtual' users can't be logged into by using this article My issue now is that before when I ran a rake command for my Ruby on Rails application running on the server, I used su to go into www-data…
user82250
64
votes
54 answers

Hidden Features of Linux

Following in the spirit of Hidden Features of PowerShell and various others on Stack Overflow, what Linux commands or combinations of commands do you find essential in your work? Also See: Hidden Features of MySQL Hidden Features of PowerShell…
Chris Bunch
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64
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9 answers

Deleting All Partitions From the Command Line

How do you delete all partitions on a device from the command line on Linux (specifically Ubuntu)? I tried looking at fdisk, but it presents an interactive prompt. I'm looking for a single command, which I can give a device path (e.g. /dev/sda) and…
Cerin
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64
votes
7 answers

How do you wait for an exe to complete in batch file?

I'm trying to create a script to execute an exe on shutdown in order to install sp1. my script goes something like (not actual bat script). If installed GOTO END Install.exe END: My problem is that when it runs, it starts the installer, then…
Kravlin
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64
votes
7 answers

Hostnames - What are they all about?

I've recently been "forced" to perform some sysadmin work, while this isn't something that I absolutely love doing I've been reading, experimenting and learning a lot. There is one fundamental aspect of server configuration that I've not been able…
Alix Axel
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64
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6 answers

How to rename a MySQL database?

How to rename a MySQL database? The MySQL online manual has said about the RENAME DATABASE command (this documentation page has been removed by Oracle some time ago): This statement was added in MySQL 5.1.7 but was found to be dangerous and was…
nalply
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