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1500 questions
54
votes
2 answers

How do view older journalctl logs (after a rotation maybe?)

I am running docker on ubuntu 16.04 and would like to view the logs. However, I am unable to view logs after what I am guessing is some sort of rotation or the logs grow to a certain size. I have not made any changes to my journald.conf, so I am…
jdf
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54
votes
4 answers

What is the current state (2016) of SSDs in RAID?

There are plenty of resources available online that discuss using SSD drives in RAID configurations - however these mostly date back a few years, and the SSD ecosystem is very fast-moving - right as we're expecting Intel's "Optane" product release…
Dai
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54
votes
6 answers

"No command specified" from re-imported docker image/container

I am trying to take a docker container from one machine and run it on another and encountering this error: "Error response from daemon: No command specified". Below is a simplified example showing the problem: docker --version Docker version 1.10.1,…
Greendrake
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54
votes
3 answers

get notification when systemd-monitored service enters failed state

I need to have network messages sent when a systemd service I have crashes or is hung (i.e., enters failed state; I monitor for hung by using WatchdogSec=). I noticed that newer systemd have FailureAction=, but then saw that this doesn't allow…
Display Name
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54
votes
2 answers

Convert value of an Ansible variable from lower case to upper case

I am working on a playbook to join linux systems to Active Directory. I can't seem to find a way to convert the value of ansible_hostname to uppercase. One of the commands I need to run requires the hostname to be supplied in uppercase.
grahamjgreen
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54
votes
12 answers

Docker COPY issue - "no such file or directory"

In my Dockerfile I have the following 'COPY" statement: # Copy app code COPY /srv/visitor /srv/visitor It should go without saying that in my host system, under the "/srv/visitor" directory, there is indeed my source code: [root@V12 visitor]# ls…
dlyk1988
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54
votes
4 answers

EPEL Repo for CentOS 6 causing error

I've got a VM running CentOS 6 (64bit) and I'm attempting to add the EPEL repo like usual to install various packages as I do quite regularly. Today, I'm experiencing some strange errors yet I'm doing absolutely nothing differently. I'm adding EPEL…
Tom Wilson
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54
votes
4 answers

nice sudo or sudo nice?

is there any difference between running an intensive task over sudo with the following commands?: nice sudo [intensive command here] sudo nice [intensive command here] BTW this is for Linux 3.x.
54
votes
7 answers

How to get e-mail from (failed) cron-jobs in Ubuntu?

I create cron-jobs in Ubuntu by placing the executable in one of /etc/cron.{daily,hourly,monthly,weekly}. There are lots of directories starting with cron: kent@rat:~$ ls -ld /etc/cron* drwxr-xr-x 2 root root 4096 2009-06-06 18:52…
Deleted
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54
votes
4 answers

Can I make rsync output only the summary?

I use rsync to backup a directory which is very big, containing many sub-directories and files, so I don't want to see the "incremental file list". I just want to know the summary in the end. If I use the argument -q, nothing is output at all. Can I…
horsley
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54
votes
6 answers

Is there a way to permanently set the font and window size in PuTTY?

When I log in with PuTTY, I always have to: change settings appearance font change 8 resize window so that I can see enough text to work with the log files. I don't see where I can save these settings to my saved session. Is this…
Edward Tanguay
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54
votes
4 answers

Is there a built-in command-line tool under Windows like wget/curl?

I come from a Linux/Unix background and I have been wondering if Windows has a binary that can download files from the console. I would like to automate a certain process and one of my requirements it to not install much software, but use the…
carlspring
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54
votes
6 answers

How do I access the list of currently logged on users through Terminal Services Manager in Windows Server 2012?

In Windows 2003 and 2008 we had Terminal Services Manager (see screenshot below). However in Windows server 2012 it's gone. Does anyone know how to access the list of currently remotely logged on users in Windows 2012 through a similar tool or some…
54
votes
6 answers

Can an SSL certificate be on a single line in a file (no line breaks)?

SSL certificates by default have line breaks after 67 characters. I'm trying to create SSL certificate files using Chef. Essentially I want to create the entire certificate file from a string variable without any line breaks. I've tried this a few…
wrangler
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54
votes
5 answers

Is greylisting still an efficient method for preventing spam?

I've used greylisting on my servers for many years, but I don't know how effective it is nowadays. Is it still good for fighting spam in 2012? Or is the typical spammer MTA capable of resending greylisted emails now?
neu242
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