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1500 questions
285
votes
5 answers

Redirect, Change URLs or Redirect HTTP to HTTPS in Apache - Everything You Ever Wanted to Know About mod_rewrite Rules but Were Afraid to Ask

This is a Canonical Question about Apache's mod_rewrite. Changing a request URL or redirecting users to a different URL than the one they originally requested is done using mod_rewrite. This includes such things as: Changing HTTP to HTTPS (or the…
Kyle Brandt
  • 84,369
284
votes
13 answers

Can I nohup/screen an already-started process?

I'm doing some test-runs of long-running data migration scripts, over SSH. Let's say I start running a script around 4 PM; now, 6 PM rolls around, and I'm cursing myself for not doing this all in screen. Is there any way to "retroactively" nohup a…
ojrac
  • 2,943
283
votes
7 answers

command for checking Apache configuration

I'm looking for a command that checks the validity of the config files in Apache server on both Debian and RHEL distros. I need to do this prior to restart, so there will be no downtime.
Sigtran
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280
votes
4 answers

How to remove an image tag in Docker without removing the image itself?

Let's say I want to tag a Docker image, and make a typo. How do I remove the tag without removing the image itself? Neither the manpages nor the Docker documentation mention removing tags. docker tag 0e5574283393 my-imaj docker tag 0e5574283393…
Mihai
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280
votes
160 answers

Useful Command-line Commands on Windows

The aim for this Wiki is to promote using a command to open up commonly used applications without having to go through many mouse clicks - thus saving time on monitoring and troubleshooting Windows machines. Answer entries need to…
dance2die
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278
votes
45 answers

What are the obstacles to providing reliable Internet access and Wi-Fi at large tech conferences?

Every tech conference I've ever been to, and I've been to a lot, has had absolutely abysmal Wi-Fi and Internet access. Sometimes it's the DHCP server running out of addresses. Sometimes the backhaul is clearly inadequate. Sometimes there's one…
Joel Spolsky
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277
votes
3 answers

Moving an already-running process to Screen

My office job routinely sees me connected to a Linux box via VNC. Sometimes I start a remote job on the console, and realize later that it runs much longer than expected. (Should have started that one under Screen in the first place...) I don't want…
DevSolar
  • 2,946
277
votes
6 answers

how to download the ssl certificate from a website?

I want to download the ssl certificate from, say https://www.google.com, using wget or any other commands. Any unix command line? wget or openssl?
RainDoctor
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275
votes
6 answers

How to assign permissions to ApplicationPoolIdentity account

In IIS 7 on Windows Server 2008, application pools can be run as the "ApplicationPoolIdentity" account instead of the NetworkService account. How do I assign permissions to this "ApplicationPoolIdentity" account. It does not appear as a local user…
Triynko
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275
votes
2 answers

Do systemd unit files have to be reloaded when modified?

Let's say I write a mine.service file. Then I use systemctl enable mine.service. If I later decide to edit mine.service, do I have to tell systemd that mine.service was changed? If so, how do I do that?
425nesp
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275
votes
3 answers

What is archive mode in rsync?

I know you can use -a or --archive to activate archive mode when using rsync. Unfortunately, I have no idea what archive mode is supposed to do, and the man page is not at all explicit about what this is: equals -rlptgoD (no -H,-A,-X) Can you…
allyourcode
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271
votes
2 answers

Why is "chmod -R 777 /" destructive?

This is a Canonical Question about File Permission and Why 777 is "destructive". I'm not asking how to fix this problem, as there are a ton of references of that already on Server Fault (reinstall OS). Why does it do anything destructive at…
samwise
  • 2,413
270
votes
12 answers

List all DNS records in a domain using dig?

My company runs an internal DNS for mycompany.example There is a machine on the network that I need to find, but I’ve forgotten its name. If I could see a list, it would probably jog my memory. How can I list all of the domain records for…
Runcible
  • 3,275
269
votes
15 answers

I've inherited a rat's nest of cabling. What now?

You know, you see pictures like below and sort of chuckle until you actually have to deal with it. I have just inherited something that looks like the picture below. The culture of the organization does not tolerate down time very well, yet I have…
269
votes
2 answers

Linux command to inspect TXT records of a domain

Is there a linux shell command that I can use to inspect the TXT records of a domain?
learningtech
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