Questions specifically about Linux but not specific to a particular distribution. If the question could apply to any Unix-like system, specify your Linux distribution in the body of your question but do not use the /linux tag.

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2
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0answers
57 views

Prevent large file write from freezing the system

So on my Linux desktop, I'm writing some large file either to a local disk or an NFS mount. There is some kind of system buffer that the to-be-written data is cached in. (Something in the range of ...
2
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0answers
73 views

How to restore casper-rw file to a casper-rw partition

New to Linux and using Mint 17.2. Started with persistent Live USB that ran out of space after a week. So made a backup of everything (entire filesystem) including the casper-rw file, created new Live ...
2
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0answers
81 views

How to restrict openvpn clients to communicate with other vpn clients

I have this Openvpn scenario.. I have Lot of openvpn clients connected to my server, All i want is to restrict client to client communication. for eg. i have ...
2
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0answers
61 views

What is the effect of ACLs/umask on the permissions of the executable file generated by gcc?

I have been wondering how gcc determines the resulting file permissions of the executable file being generated. To gain some insight, I considered a minimalistic program test.c #include ...
2
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0answers
172 views

Portable way to parse /proc/meminfo

I'm having trouble finding a generic code that work, here, for both CentOS 5/6 and CentOS 7 versions pc the /proc/meminfo file. I Want to compute the "Real Used memory" like free does. (amounts ...
2
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0answers
33 views

Why is my traffic not encrypted when using pam_radius_auth?

I'm experimenting with Freeradius and have configured an ssh gateway to use pam_radius_auth to my ldap servers. In /etc/pam_radius_auth.conf I have: 10.1.1.21 ny3fa4bu7my6ku7 3 10.1.1.22 ...
2
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0answers
39 views

Detect which program is blocked by firewall

The linux firewall can show a lot of information in the LOG target, for example via --log-uid. How can the executable doing the network call be logged, too? I did not find anything in the FAQ, the ...
2
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0answers
75 views

NUL entry in syslog?

My servers went down on the 30th. It just came back online today. At first I thought it was the router because the router the server is connected to is a bit squirrely but when I checked syslog I have ...
2
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0answers
34 views

Random pieces of ancient hardware not working together (Mac G5, Sun network adapter)

This is probably some kind of weird esoteric hardware combination but it's not why I did it. It's just what I had lying around. I have a 2x 2ghz Mac G5 and I can't really bring myself to part with it ...
2
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0answers
178 views

Cannot boot into Linux off live USB

I am trying to dual boot Linux on my laptop (Dell XPS 15) which is running Windows 10 Pro. I did not have any problem dual booting the two operating systems on my desktop. I cannot boot up ANY Linux ...
2
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0answers
26 views

What is “state-object” in cgroups

I am gathering some idea about lxc, kernel name spaces and cgroups. While reading man lxc-cgroup, i find : lxc-cgroup gets or sets the value of a state-object (e.g., 'cpuset.cpus') in the ...
2
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0answers
434 views

Login/logout loop on Ubuntu 14.04

I am running Ubuntu 14.04 inside VMware workstation 11.1. I testing changing the color depth and now I am hitting a login/logout loop. When the login screen comes up I select my account, type in the ...
2
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0answers
61 views

running cron on a chroot

For my web development I use a debootstrap'ped Debian with sysvinit, I start apache2/mysql manually only when I need to work. Now for a new project I require to run some scheduled task for which I ...
2
votes
0answers
39 views

How to trap spam sent from certain top-level domains?

I'm getting a lot of spam from eu TLD Maybe I could have put a rule set giving a score of say 2.5 or 3 for any mail originating from the .eu TLD; then this score + other factors could have made it ...
2
votes
0answers
187 views

Disk I/O latency using /proc/vmstat file

How do I calculate disk read and write latency in Linux? Is it possible to do the calculation using /proc file system? I am using iostat and vmstat command. But I do not understand how the ...
2
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0answers
75 views

Freeradius server for multiple vendor network

We have been using network switches from Enterasys and for logging in to these switches, with AD credentials, we have setup a freeradius server on RHEL 6.5 server, that is working absolutely fine. ...
2
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0answers
162 views

bluez paired but disconnected

I'm running bluez=4.99-2 on a Raspberry with Raspian installed and an old usb dongle 0a5c:200a Broadcom Corp. BCM2035. I use an Android device to connect to it, the dongle doesn't support sspmode so ...
2
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0answers
69 views

df human-readable calculation

I was wonder why there is a difference between the reported size of a filesystem with df -h and calculating it manually. for example: The size according to LVM: # lvdisplay system/var | grep -i ...
2
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0answers
8 views

Get information about CVMFS transfers and files in cache

I am using CVMFS (CERN Virtual Machine File System), and it works generally pretty good, but sometimes it takes a while to access a certain file, and I would like to know what is going on. Is it ...
2
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0answers
65 views

More than 255 Linux GRE tunnels

Is it possible to set up more than 255 GRE tunnels in Linux? It seems that 255 is the default maximum, but is there any way to increase the limit?
2
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0answers
95 views

Add disks to encrypted LVM partition

If I increase my current encrypted (dm-crypt)LVM partition by adding another disk to it, is the new disk also encrypted or do I need to setup dm-crypt on it as well?
2
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0answers
260 views

X11 controlling root window or setting a window to be the background window (wallpaper)

I would like an animated background image. Or better, to make an application be the background, with no interactivity, so I don't accidentally click on it. I've seen many discussions about setting ...
2
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0answers
125 views

Which boot loader is commonly used on Linux distributions and why?

I have been using Ubuntu on my local machine and occasionally running Debian and other Linux distributions for experience. Until recently I thought GRUB 2 is far common, but that was misleading. ...
2
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0answers
134 views

EDID - help to detect proper DPI and refresh rate values

I just tried to extract EDID file data with read-edid util; The thing is the output shows : $sudo get-edid | decode-edid ... Manufacturer: AUO Model 20ec Serial Number 0 Made week 0 of 2013 EDID ...
2
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0answers
156 views

Magnetic stripe reader on Debian

I have recently aquired a USB magnetic stripe card reader. When used on Windows, I swipe a card, it acts as a keyboard and types out whatever is on the magstripe. However when used on Linux (Ubuntu ...
2
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0answers
99 views

Screen is shaking/wobbling in Debian 8.1

I just installed Debian 8.1 on my Lenovo Y70 laptop. Besides other driver problems, one of the problems I can't get rid of is this shaking/wobbling screen. I tried to install intel drivers and xorg ...
2
votes
0answers
66 views

How to replace faulty device on RAID5

I wanted to replace a corrupted raid5-device on my linux system (opensuse 13.2) but missed the step of set-faulty/removing the device (/dev/sdc1). So i accidently just switch the device with a cloned ...
2
votes
0answers
29 views

Significance of Linux kernel's default_console_loglevel

What is the significance of default_console_loglevel in Linux? Commonly I see it described as the default value of console_loglevel. However, what that means I haven't seen explained anywhere. ...
2
votes
0answers
72 views

radeon power management

Checking upon /sys/kernel/debug/dri/0/radeon_pm_info, puzzled me. It seems that there are only one power level and some are disabled. It shows : uvd disabled vce disabled power level 0 sclk: ...
2
votes
0answers
86 views

How to check flash memory for ECC errors from the Linux command line

Is there a way to check flash memory for ECC errors from the Linux command line? Note that I do not want to correct ECC errors. I just want to detect errors and list page addresses where they occur.
2
votes
0answers
50 views

What happens if the last process in a namespace exits?

I am running Linux. I have a single process in a mount namespace. I did in this process a mount -t tmpfs tmpfs /mountpoint. What happens if the process exits and there are no more processes in ...
2
votes
0answers
51 views

SD card protected area

The Wikipedia article on SD cards mentions that about 10% of the capacity of an SD card is a so-called protected area, which is used for the security-related features of the card. Let's say I don't ...
2
votes
0answers
80 views

check the current backlog queue size

The sysctl netdev_max_backlog sets a limit to the maximum number of packets allowed in the kernel's backlog queue. Is there a way to check the current queue size (i.e., how many packets are currently ...
2
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0answers
226 views

Restore Btrfs snapshot from subdirectory to parent

I have a Btrfs partition which has a single subvolume at the top level (/root). It has subvol=root option in /etc/fstab. Every week, I take a readonly snapshot into /root/snapshots/... using: btrfs ...
2
votes
0answers
71 views

How to use blktrace to monitor the eMMC Flash access pattern?

I'm trying to simulate a FTL(Flash Translation Layer) algorithm and evaluate its performance. What I need is a trace file of a flash access(containing information about block and page access). I'm ...
2
votes
0answers
160 views

How to resolve dracut problem when intall Fedora 21

I'm Ubuntu User. But I wanted to change my OS from Ubuntu to Fedora. So I wanted to Fedora 21. But there is a problem. I'm using USB Drive to boot Fedora 21. When I try to install Fedora I get a ...
2
votes
0answers
297 views

How to understand the security context in “ls -Z”?

After referring "man ls", it shows "ls -Z" can display the security context: -Z, --context Display security context so it fits on most displays. Displays only mode, user, group, security ...
2
votes
0answers
30 views

Can't figure out what all these sd drives are

So I created a WindowsXP install using an NTFS drive in VMPlayer and now I want to make an image of it using dd. Here is the diskpart info from Windows: Then I use Kali as a live-cd and I find like ...
2
votes
0answers
62 views

Can't copy or view files with hangul on HFS+

I'm trying to copy a directory of Korean and Japanese music on a Debian Jessie box. The source file system is HFS+J (Mavericks vintage) from a dead Mac, mounted with hfstools: # mount -t hfsplus -o ...
2
votes
0answers
195 views

What does an inode for a socket contain?

I read somewhere that the inode for a TCP socket would contain the buffer space. Is that true, and if so, does it mean that the inode contains a memory address for the buffer space used by the ...
2
votes
0answers
68 views

Why can't Adobe Flash for Mac run on Linux?

As we know, Adobe no longer develops new Flash versions for Linux (except for Google Chrome, i know). It does, however, develop actively Flash for Windows and Mac. Linux can run native Windows ...
2
votes
0answers
317 views

dhcp ipv6 dynamic prefix delegation

I'm trying to setup Linux-based home gateway with IPv6 support. IPv4 configuration is finished and I'm using IPv4 NAT, ISC DHCP for addresses allocation, PowerDNS for local DNS setup, PDNS recursor to ...
2
votes
0answers
76 views

Record video from camera and get frame number on demand

I'm using avconv at the moment to store the input of my camera as an video. This works fine. Now i'm asking myself if it is possible to get the current frame number at a particular time of the video ...
2
votes
0answers
145 views

How to switch wifi channel without dropping connection?

We are developing small internet connected device that connects via wifi and does some work. It is controlled via mobile app. For configuration purposes we use wi-fi module that can work in both STA ...
2
votes
0answers
171 views

UNIX sockets vs AF_NETLINK vs Kdbus vs Binder

What are essential differences between those IPCs? Which are main use cases? Is there some consolidated comparison table between them somewhere? Something like: Protocol: AF_UNIX | ...
2
votes
0answers
42 views

Is it possible to make the right mouse button do something else in Linux Mint?

I have a cheap 2 button mouse so wanted to turn the right mouse button into my gesture button (with Easystroke). Perhaps making a double right click act as a normal right click.
2
votes
0answers
321 views

is THP good or bad for MySQL Server?

Linux kernel new feature called Transparent Huge Pages (THP) which is by default enabled on CentOS 6.x and above OS. Is THP good for MySQL DB machine? I am trying following to disabled THP but seems ...
2
votes
0answers
267 views

Running a systemd service file after the network is up to bypass an OpenVPN default gateway

I would like to add a static route using a systemd service file on system boot. I have a DMZ network on a separate 192.168 class C network reachable via my default gateway. I also use OpenVPN to ...
2
votes
0answers
633 views

How do I view multiple users groups using sssd?

SETUP OS = RHEL 6.4 Workstation System is part of an LDAP domain and was originally configured to authenticate using nscd. All recommended SSSD packages have been installed. ...
2
votes
0answers
376 views

Can I make the boot even more verbose than loglevel=7 using kernel parameters?

I have an error when booting on a machine, my machine is stuck with the error message: Booting a command list. I can see this message when I add loglevel=7 and only if I delete the quiet in the ...