New answers tagged linux
0
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Does Windows have something like journald on Linux?
Slow boots can arise from multiple sources.
Dying hard disks
Fragmented file systems.
Extra steps in the bootup process, eg more executables being loaded and initializing, and some possibly hanging.
...
0
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Setting up Linux Samba server (general problems): No permission
"The hosts allow or allow hosts parameter is one of the key advantages of Samba. It allows access control of shares on the ip-address level. To allow only specific hosts to access a share, list ...
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create symbolic link in directory with no write permission
You have to access the directory with elevated permissions, or from a user or group that has write access to the directory, such as the owner or the owners group.
Even if you own the file in a ...
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Sink file like /dev/null
I would have said tmp, since the files there are supposed to be purged, after 30 days. Perhaps you can update the time for which tmp stores files in the settings somewhere, but if the application is ...
3
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How routers deal with only one external IP?
From googling I understand that all routers do is performing NAT
NAT is still an "add-on" feature on top of actual routing. When a reply comes in, after NAT it still follows the regular ...
- 417k
0
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create symbolic link in directory with no write permission
Modifying the file is a file permission action. Deleting the file is a directory permission action. Replacing a file is deleting a file and writing a new file, and both these actions are directory ...
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How routers deal with only one external IP?
They keep track of the ports at each live device level.
The external ip is on the network of the wan, so connections to it are going to be handled by the router over a specific local and remote port ...
3
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How routers deal with only one external IP?
The following is a very basic explanation.
Your devices uses private addresses. Private addresses are subnets/networks with the following IP addresses (see RFC 1918):
10.0.0.0 to 10.255.255.255
172....
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2
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Sink file like /dev/null
The post
How can I create a /dev/null-like "blackhole" directory?
suggests this :
This isn't supported out-of-the-box on any unix I know, but you can do pretty much anything with FUSE. ...
- 446k
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1
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iptables drop all packets that do not come from two specific subnets
drop all packets that do not come with a source IP in the subnets 11.2.4.0/24 and 11.2.3.0/24
To avoid any misinterpretation: drop all packets that do not come with a source IP in the subnets (11.2.4....
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tmux %if %else %endif syntax misbehaving when using a String Comparison statement on a format variable invoked on .tmux.conf
< and > within tmux perform a string comparison (sorting), character by character. The string 2 is indeed "greater" than 10 because the first character 2 > 1 (the rest of the string ...
- 417k
0
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Unprocessed orphan inode list in VirtualBox VM
I was facing the same issue on an AWS EC2 machine. To complicate the resolution, the volume that was affected was the root volume of the EC2 instance. Hence the device was failing to boot and SSH was ...
- 101
3
votes
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Allowing world access to a Raspberry PI behind a home router
The Pi creates an SSH tunnel/VPN with a server on the internet. I then connect to that server to to connect to the Pi. Are there people who offer such a service?
There are hundreds of companies that ...
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0
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How can I view results of my cron jobs?
Just run journalctl -u cron.service (and then hit SHIFT + G to go to the bottom of the page if you need).
While it is usually better to redirect the output of your cron script somewhere intentional, ...
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Fit 2 A5 pdf into ONE PAGE A4 Landscape
I joint a link to my code and 16 pdf A5 files to work with it:
http://panificiochicco.it/chifelio/gsrif/filespip.php
Make +x forpdf16.sh in the same dir of *.pdf files
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Why does `rsync` show directories even if it does not make any transfer
You need to include the --prune-empty-dirs flag (-m).
This option tells the receiving rsync to get rid of empty directories from the file-list, including nested directories that have no non-...
- 2,804
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How to copy Files from One folder to another using third folder as a reference ? (Ubuntu/Linux/rsync)
This command will implement your requirement assuming that the specified directories 1, 2, 3 are in the current directory ($PWD). This isn't necessary for the source and destination, but the ...
- 2,804
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Where is vmlinux on my Ubuntu installation?
vmlinux file is part of what's called Debug Symbol Packages.
Here's a good reference: https://wiki.ubuntu.com/Debug%20Symbol%20Packages
First run this:
echo "deb http://ddebs.ubuntu.com $(...
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Assign IP and a testing Domain to a VirtualBox
This article helped me to forward ip address to access my linux debian virtualbox machine through my hosts browser. And also to assign a test domain to that ip address on host machine edit
Linux: /...
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Fit 2 A5 pdf into ONE PAGE A4 Landscape
From alls your reponse I understand that I had no correctly expose my initial question: I know how create mysingle.pdf, A5 formatted with "wkhtmltopdf" command. I know how to separate ...
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What happens (how to control what happens) to the unused part (unused tail) of a block when writing a small file to a larger block?
Filesystem blocks (or clusters, you name it) are "backed" by logical blocks of a storage drive. With at least command sets used in modern storage interfaces (ATA/SCSI/NVMe/...), there is no ...
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What happens (how to control what happens) to the unused part (unused tail) of a block when writing a small file to a larger block?
When a process performs a buffered write, the bytes are copied into the page cache, and then eventually the dirty page will be written to disk. This can happen for a number of reasons; the program ...
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0
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Fit 2 A5 pdf into ONE PAGE A4 Landscape
Supposing you can create with wkhtmltopdf a normal A4 file, the following pdfjam[1,2,3] command should work as per your wishes
pdfjam --landscape --signature 16 main.pdf
Note that signature has to ...
- 18.6k
0
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How to reliably attach to session DBUS over ssh?
More practical way is to use ssh with X forwarding. And it works for me just fine.
ssh -X alt-user@localhost
Of cause, one has to setup ssh properly for this to work. But it is described very well on ...
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1
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Linux--What program is responsible for the "Battery Low" notification, when I have plenty of battery left?
It's a bug in the power manager due to battery status 'flapping', see this:
power manager notifications repeating incessantly ... power problems?
I'm still looking for a nice solution to this...
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0
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Grub doesn't show OS selection menu when booting a dual boot setup
This could be caused by grub not detecting other installed partitions.
To fix this open the grub file
sudo gedit /etc/default/grub
Then enable the os-probe by adding the following line in the grub ...
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1
vote
Accepted
Linux UDP server always show 127.0.0.1 as source IP
The netcat tool (all of its variants, including nmap's netcat) has no feature to handle this for UDP.
Due to how the BSD socket API is implemented, contrary to TCP, by default UDP doesn't keep state ...
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0
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Is it possible to get `ps` to render thread names in wide mode?
You can't.
Thread names are limited to 16 bytes in Linux kernel. Which is 15 characters and the C-string \0 (null) terminating char. Which can also be seen in your example of OkHttp TaskRunn ...
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0
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ssh multi-hop... adapting command to ssh config file
To ssh into server B from server A with the same username
Host target
HostName <serverB_hostname>
ForwardX11Trusted yes
LogLevel verbose
User <username>
ProxyCommand ssh <...
1
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What happens (how to control what happens) to the unused part (unused tail) of a block when writing a small file to a larger block?
A long time ago, de-allocated sectors with sensitive data
on a HDD could be read by writing a small file to the
disk on top of the existing data, then reading in the
entire sector, as it is allocated ...
- 446k
2
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What happens (how to control what happens) to the unused part (unused tail) of a block when writing a small file to a larger block?
I can not comment on EXT4 specifically but,
Observation on NTFS formatted drives:
Assume 4KB clusters and cluster only partially used, the 'tail' contains zeros. Here we see the last two bytes of a ...
- 3,308
0
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Make Windows Detect a Hard Drive in a Similar Way as Linux Does
The main issue with Windows is that it will try to mount everything it recognizes. So basically any volume formatted with a file system it can work with. This results in two problems:
Windows will '...
- 3,308
0
votes
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Outgoing UDP packets don't reach the host from VM after certain time
Setting pivpnPERSISTENTKEEPALIVE=25 in /etc/pivpn/wireguard/setupVars.conf and creating the client configs again like described here seems to solve the problem.
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0
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QEMU (with virtmanager) boots to uefi shell when trying to install windows 11
In my case, I believe I had let the "Press any key to boot from.." screen timeout. I reboot the VM, and pressed a key when prompted, and it worked fine. This is corroborated by FAQ someone ...
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-2
votes
Kali Linux live USB with WiFi adapter support?
To get your Kali Linux OS to recognize and use the Netgear USB Wi-Fi adapter, you can follow these steps:
Plug in the Netgear USB Wi-Fi adapter into your laptop's USB port.
Open a terminal window in ...
0
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opendkim still not working - opendkim-genkey: openssl exited with status %d
I ended up purging openssl and reinstalling sudo apt-get openssl. I had to reinstall postfix and dovecot (and maybe will need to with others too) but in the end it seems to be working now.
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1
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How can I HTTP stream a USB webcam plugged into my headless Ubuntu Server remotely?
Using https://motion-project.github.io, I could create a config file with 2 lines, and do a standard reverse proxy using NGINX.
Here is my motion.conf file:
stream_quality 98
stream_maxrate 5
...
- 111
0
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Is there an image viewer that takes images on STDIN?
With imv, e.g. on Debian bullseye:
sudo apt install imv
# it provides commands imv-x11 and imv-wayland
# e.g. with imv-x11, pipe to imv-x11, and make sure to end the command with a dash: e.g.
...
- 2,046
1
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Grant user access to create snapshots in btrfs
There does not appear to be any reasonable way to bypass this check.
I have located the permission check in the source code. It defers to the inode_owner_or_capable.
if (!inode_owner_or_capable(idmap,...
- 1,404
0
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When reading a file with `less` or `more`, how can I get the content in colors?
A simple (but multi-step) approach is to run the 'script' program, then within the script context, run your command (without piping to less), then exit the script context. You can now run less -R on ...
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1
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SSSD multiline ad_access_filter
Sadly, the basic INI file format is simply not guaranteed to support multiline anything. Individual software might implement a smarter parser, but it's not standard, and the one used by SSSD doesn't.
...
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0
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How can I see the details of Total banned of Fail2Ban?
On many distributions, Fail2Ban records every action it performs to the SYSLOG. You can double-check your /etc/fail2ban/fail2ban.conf and look for the command logtarget. On my CENTOS box, that line ...
0
votes
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find and rename base directory and files under each basedir, add a prefix
First we recreate your structure in a TesT directory
mkdir TesT; cd TesT
mkdir -p G{1,2}_BIN_REFINEMENT/marker_genes/identify/intermediate_results/marker_genes/bin.{1,2}
touch G{1,2}_BIN_REFINEMENT/...
- 18.6k
0
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Glitchy white screen after the latest ubuntu 20.04 software update
Have you tried to reinstall the nvidia-driver?
sudo apt install nvidia-driver-xxx
where xxx is the version of your nvidia-driver. You can find the version of your nvidia-driver from https://www....
- 101
1
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Does TRIM avoid the performance impact of mdadm RAID 1 on SSD?
To add to the antiquated answer, I’ve recently replaced a failed HDD on my RAID1 with an SSD, from the experimenting and research I’ve conducted, I’ve found the following:
Linux md passes through ...
- 11
3
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Make Windows Detect a Hard Drive in a Similar Way as Linux Does
Due to the inner workings of a Microsoft operating system connecting a failing drive to a computer running a Microsoft operating sytem is increasing your chances to fail as DrMoishe Pippik already ...
- 2,930
10
votes
Accepted
Can Expect make sure a certain log does not appear?
You can expect multiple things:
expect {
"license activation error" {
... mark that this happened ...
}
"System booted" {
... check if the above error ...
- 446k
0
votes
Accepted
7z2john can't be found after installation
The binary database used by locate (/var/lib/mlocate/mlocate.db)
is updated once daily by cron, so locate will not find new files,
especially if locate itself was only installed today.
You can fix ...
- 446k
0
votes
Assign IP and a testing Domain to a VirtualBox
Configure a "Host-Only" network interface in VirtualBox. It's named that way because it doesn't do built-in NAT or any other magic, but it also doesn't have any special "host only" ...
- 417k
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