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1500 questions
138
votes
24 answers
How do you make it obvious you are on a production system?
A few of us at my company have root access on production servers. We are looking for a good way to make it exceedingly clear when we have ssh'd in.
A few ideas we have had are:
Bright red prompt
Answer a riddle before getting a shell
Type a random…
Sionide21
- 1,553
- 3
- 11
- 10
137
votes
13 answers
How do I get apt-get to ignore some dependencies?
How do I make apt-get ignore some dependencies? For example, I wanted to install mailx so I can use it to send email from cron scripts/report-generating tools. However, installing mailx also installs exim4 and a whole bunch of dependencies (I…
FrancisV
- 1,766
- 3
- 16
- 18
136
votes
4 answers
robocopy transfer file and not folder
I'm trying to use robocopy to transfer a single file from one location to another but robocopy seems to think I'm always specifying a folder. Here is an example:
robocopy "c:\transfer_this.txt" "z:\transferred.txt"
But I get this error…
Bill McKay
136
votes
7 answers
How to list Apache enabled modules?
Is there a command that list all enabled Apache modules?
supercobra
- 1,515
- 2
- 12
- 9
135
votes
5 answers
How does IPv6 subnetting work and how does it differ from IPv4 subnetting?
This is a Canonical Question about IPv6 Subnetting.
Related:
How does IPv4 Subnetting Work?
I know a lot about IPv4 Subnetting, and as I prepare to (deploy|work on) an IPv6 network I need to know how much of this knowledge is transferable and…
Michael Hampton
- 244,070
- 43
- 506
- 972
135
votes
10 answers
Is there an equivalent of MySQL's SHOW CREATE TABLE in Postgres?
Is there an equivalent of MySQL's SHOW CREATE TABLE in Postgres? Is this possible? If not what is the next best solution?
I need the statement because I use it to create the table on an remote server (over WCF).
vlebar
- 1,453
- 2
- 9
- 4
134
votes
7 answers
Certification authority root certificate expiry and renewal
In 2004, I set up a small certification authority using OpenSSL on Linux and the simple management scripts provided with OpenVPN. In accordance with the guides I found at the time, I set the validity period for the root CA certificate to 10 years.…
Remy Blank
- 1,995
- 3
- 15
- 11
134
votes
3 answers
Is there a way to view the members of an Active Directory group if you aren't a domain admin and can't log into to a domain controller?
Is there a way to view the members of an Active Directory group if you aren't a domain admin and can't log into to a domain controller?
Alan Hecht
- 1,463
- 2
- 11
- 10
134
votes
5 answers
Rsync difference between --checksum and --ignore-times options
Can anyone clarify the differences between the --checksum and --ignore-times options of rsync?
My understanding is as follows:
--checksum
If the file size and time match, it will do a checksum at both ends to see if the files are really…
Andy Madge
- 1,607
- 2
- 14
- 14
133
votes
5 answers
Clean way to write complex multi-line string to a variable
I need to write some complex xml to a variable inside a bash script. The xml needs to be readable inside the bash script as this is where the xml fragment will live, it's not being read from another file or source.
So my question is this if I have a…
ChrisInCambo
- 1,751
- 3
- 15
- 13
133
votes
4 answers
FreeBSD performance tuning: Sysctl parameter, loader.conf, kernel
I wanted to share knowledge of tuning FreeBSD via sysctl.conf / loader.conf
/ KENCONF / etc. It was initially based on Igor Sysoev's (author of nginx)
presentation about FreeBSD tuning up to 100,000-200,000 active connections.
Newer versions of…
SaveTheRbtz
- 5,691
- 4
- 32
- 45
133
votes
3 answers
How do I reattach to Ubuntu Server's 'do-release-upgrade' process?
I accidentally pressed Ctrl+C during Ubuntu Server's do-release-upgrade process. I'd dropped to a shell to compare a .conf file in /etc/. When I pressed Ctrl-C, it asked whether I wanted to try to reattach to the upgrade process, but it failed to do…
Alex Leach
- 1,697
- 3
- 16
- 18
132
votes
4 answers
What significance does the user/host at the end of an SSH public key file hold?
I can’t figure out why does an SSH public key file generated by ssh-keygen have a user and host at the end of it.
Example: id_rsa.pub
ssh-rsa ... rest of file ... /CA9gyE8HRhNMG6ZDwyhPBbDfX root@mydomain
Notice the root@mydomain at the end of the…
Basil A
- 2,060
- 3
- 18
- 18
132
votes
3 answers
What does Apache's "Require all granted" really do?
I've just update my Apache server to Apache/2.4.6 which is running under Ubuntu 13.04. I used to have a vhost file that had the following:
AllowOverride All
But when I ran that I…
John Crawford
- 2,005
- 3
- 15
- 9
132
votes
7 answers
Does Windows have a built-in ZIP command for the command line?
Since Windows Explorer (since at least Windows XP) has some basic support for ZIP files, it seems like there should be a command-line equivalent, but I can't seem to find any sign of one.
Does Windows (XP, Vista, 7, 8, 2003, 2008, 2013) ship with a…
Electrons_Ahoy
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- 3
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