Questions tagged [linux]
Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.
38,564
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Facing NFS file transfer issue, file gets truncated
I am getting this error while transferring files using NFS, and the file size is getting truncated
Can anyone give me a hint? We tried 2GB, and the file gets truncated at 400 MB.
Jun 20 11:09:22 ...
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10
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1
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Multiple Reverse SSH Tunnels using Single Port
I am able to accept reverse SSH connections from multiple remote systems on a single server using a port for each connection:
Remote A: ssh -fN -R5000:localhost:22 user@server-ip -p22
Remote B: ssh -...
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1
vote
1
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906
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First Boot Script for variety of platforms
I'd like to make a firstboot script for CentOS 5/6 and Ubuntu 12.04/12.10/14.04. If possible, I'd like to use one method to trigger this script to run.
From what I can tell, this rules out chkconfig,...
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3
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Linux CLI server with a virtual windows machine running? [closed]
I have a ubuntu CLI server and I am wondering if it's possible to install a windows machine on a CLI server?
My hope is that I can take a pre-made VirutalBOX or VMware image and put it on my Ubuntu ...
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-1
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1
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Suse Desktop on EC2/Azure
I run a Suse Desktop Edition Instance on MS Azure, then installed NoMachine(NX) free ver 4.2.25, finally tried to connect from my local PC(OSX), but failed
Actually, I succeeded this with ...
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0
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Nginx proxy pass not working sometimes
I have a proxy server (ubuntu) that can accessible via my global IP (not have domain).
For Example 85.45.0.12:6021 and this reverse to local server. Local server (10.0.0.25) installed tomcat and ...
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1
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ssh session dies after three hours on inactivity
I usually leave my PuTTY terminal window open during the day and lock the screen when I go to lunch or leave to go offsite. Lately though when I come back, my ssh session had died. Even though I use ...
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Auto provisioning with IPMI
I have been looking for a way to auto provision servers using IPMI. I want to basically have a preconfigured linux O.S. and provision it to servers over the IPMI network. I read on a few software ...
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0
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Postgres 9.3 on Linux - Resource utilization - Multiple vs one service services
I'm consolidating multiple Linux boxes running Postgres into one box.
Given the way Postgres handles resource utilization, would one single server service handling all the databases provide a much ...
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4
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BTRFS: deleting a volume
A week ago, I created a BTRFS pool using two flash drives (32GB each) with this command: /sbin/mkfs.btrfs -d single /dev/sda /dev/sdb. Then I realized that I should have used the partitions /dev/sda1 ...
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dump tcp connections without tcpdump
On a centos box, I like to dump tcp connections - I would like to see if a server tries to send requests to a certain IP. Usually tcpdump would do the trick - but tcpdump is not installed, and ...
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Plesk 12 Linux Server Mail Spam Issue [closed]
I'm running multiple websites on my dedicated server, and for one website in particular where users signup and then must verify their email address, I'm getting reports from my client that a small ...
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2
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updating, upgrading debian linux server except a package
I was looking for a command line to update/upgrade my VPS with the exception of the web server software. I have Nginx v.1.4.7 on my VPS and don't want it to get updated/upgraded when I run any update/...
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ZFS on linux upgrade from 0.6.2 to 0.6.3 made my zpool unreadable help translate CentOS to Ubuntu commands
After upgrading my ubuntu 13.10 server using sudo apt-get upgrade and rebooting, my zpool wouldn't show.
messier@ANDERSON:~$ sudo zpool status
no pools available
messier@ANDERSON:~$ sudo zpool import
...
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3
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Is it possible to get any kind of unique identifier for the Infiniband switch that a particular Linux box is connected to?
I am trying to identify which Infiniband NIC's are connected to which switches, in a manner that is very similar to this question.
However, the solution proposed there is not working for Mellanox ...
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How to view network resources used by a thread in Linux
I am trying to check the network resources used by a thread but unable to figure out how. lsof only allows us to give the pid. I checked under /proc/pid/task/thread/ but could not find anything ...
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3
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Update from zfs-0.6.2-1.el6.x86_64 to zfs-0.6.3-1.el6.x86_64 has made by zpool unreadable
After running # yum update zfs and restarting my CentOS 6 ZFS on Linux system can no longer see or interact with it's zpools.
# zpool status
no pools available
# zpool import
zpool: ../../lib/libzfs/...
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5
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1
answer
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Should new Linux VMs under ESXi 5.5 mount their filesystems with discard option?
When creating new Linux virtual machines using recent (>= 2014) distributions in VMware ESXi 5.5, should they mount their filesystems with the discard option ?
I make the assumption that the VM's ...
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hostname command returns nothing on ipv6 host
I have an RHEL host that is dual stacked for ipv4 and ipv6. Ipv6 is the primary, including all DNS records for the host. Ipv4 is a fall back to reach ipv4 only networks, its even behind an ipv4 NAT.
...
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0
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actual disk iops and write merging
/dev/sdb has LVM and exposes a single logical volume, dm-0.
While writing to dm-0, /proc/diskstats reports:
# of writes completed
sdb 29646717
dm-0 131315099
# of writes merged:
sdb 101668283
dm-0 ...
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1
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Linux - KVM - very slow disk io
The I/O performance of my new server is pretty low. I Googled and tried everything I can imagine. First of all, here are the Hardware Components:
AMD Opteron(tm) Processor 6344
4x Seagate ...
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1
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Healthy Linux machine immediately went down
This is the last log entry in /var/log/messages and after this the machine has been stopped. How can I debug why the machine has been stopped?
I am not sure but maybe the system stops comes from the ...
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2
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Make kernel modules available that have been deactivated on Fedora
Edit: I turned Cristians answer into a script which does everything automatically: https://github.com/frans-fuerst/magic/blob/master/fedora-activate-can.sh
I need some kernel modules which are ...
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3
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How to limit amount of email sent by postfix to certain domains and control it by using mail header?
Goal
I'm looking for a solution to limit rate of e-mails sent to specific e-mail operator (several Top-Level domains, all of them I know) on hourly basis. I also need some way to control the rate on ...
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1
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Iptables counters restore, when using quotas, not working as expected
I've set a quota for a certain computer:
iptables -A FORWARD -d 192.168.1.10 -m quota --quota 500000000 -j ACCEPT
iptables -A FORWARD -d 192.168.1.10 -j DROP
This works as expected. When the limit (...
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1
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138
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ifconfig TX/RX on gateway
I have a linux gateway which does nat for a couple of machines behind it.
I got complains that we have way more monthly traffic gigs more than we should so the first thing I look was check the ...
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Increase bandwidth per connection on a server
Requirement:
I am load testing Rabbit MQ by generating a large number of requests/sec to the server (Server config: 8 core, 16GB).
To achieve the above, I am generating load from a client machine at ...
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5
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Kernel stack trace to source code lines
Given a kernel stack trace as below, how do you determine the specific line of code where the issue occurred?
kernel: [<ffffffff80009a14>] __link_path_walk+0x173/0xfb9
kernel: [<...
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Recovering files without .encfs6.xml
I've lost my .encfs6.xml file for a encfs volume. I still know my passphrase. Is there anyway to regenerate the .encfs6.xml based on similar volumes and the passphrase? Any chance of brute-forcing?
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Postfix, schedule batches of email to be sent
Is it possible to have postfix limit the amount of emails it sends at once and when there is larger than x email, send them out in timed batches (wait 5 minutes, send another 50, something like that)?
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Set up Ubuntu FTP with root access to whole server
I've been trying to set up Ubuntu 12.10 with FTP to give the A user access to read/write any file on the server.
I understand some people discourage root access for this, but at this stage I am more ...
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Resolve all external addresses to an internal address when an internet connection is missing
I am using a raspberry-pi running ArchLinux with a WiFi router to provide an access point for locally-hosted web content. I am running a DHCP server. When the Pi is plugged into an internet connection,...
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5
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/etc/passwd shows user in a group, but /etc/group does not
I want to verify that the user account filesender_1 is a member of the group valid_senders.
When I look at /etc/group, filesender_1 is not there:
valid_senders:x:12345:production_1
I read this as "...
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2
answers
20k
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Fork a process inside a bash shell script
I've a simple shell script like
#!/bin/bash
sh -c "sleep 60" &
exec sleep 120
In using the pstree command, I found something like
`-sleep(11681)---sleep(11682)
The first sleep is due to the ...
- 6,041
1
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1
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NIDS on bridged firewall
I have a firewall (Debian Stable 7.5) which works in bridged mode. The interfaces eth0 (WAN) and eth1 (LAN) are linked with the bridge interface br0.
Can I deploy a NIDS (eg. Snort) on this server? ...
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Linux commands are hanging on ec2 instance
We are having a VPC setup for our staging environment. In this we have attached an elastic ip to one instance & rest of the instances are connected through this.
Now today when we restarted our ...
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2
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Linux locale: en_US.UTF-8 vs en_US
I usually config my ubuntu via
sudo locale-gen --purge en_US.UTF-8
And I've the installed locales
# locale -a
C
C.UTF-8
en_US.utf8
POSIX
Is it okay since I am missing en_US?
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SaltStack minions require restart after replacing master
I'm using SaltStack to manage several servers on EC2, including both Linux and MS-Windows installations. The master server is deployable in its entirety (using cloud-init) and when I change the ...
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Created 100GB ec2 instance, but only shows 10GB?
I just created a new EC2 instance of 100gb with only 1 storage disk.
However, my df -h output shows the following :
[root@ip-10-252-37-164 ~]# df -h
Filesystem Size Used Avail Use% ...
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Is it possible to use OpenVPN tap device and have latency less then 100ms?
I've just setup OpenVPN server with the following config:
daemon
server-bridge
push "route 0.0.0.0 255.255.255.255 net_gateway"
proto udp
port 1194
dev tap21
comp-lzo adaptive
keepalive 15 60
verb 3
...
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Unusually high nfs_inode_cache
My server is experiencing a high usage of nfs_inode_cache = 11G , im trying to figure out what's consuming all this , i know already that directories with large numbers of entries and deep directory ...
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How to route to next server? [closed]
I must route all traffic from first server to second server and next to third server.
Like this:
server1 -> server2 -> server3
I use Debian Wheezy.
Can anyone tell how to do this with iproute?
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Directory size limit [closed]
In Linux, it's possible to limit the size of a partition, for example with quota. But does a way to limit directory size exist?
For example, I have a directory, let say /mnt/foo/bar, which is not a ...
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How do I change the hostname in a fhgfs management node?
FHGFS is a high performance parallel file system typically used in clusters.
How would you go about changing the hostname of the management server without breaking connection between the storage and ...
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1
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Jetty JMX setup for remote access
I am having some issues getting JMX working on Jetty(9.1.3.v20140225), so I have had a read over the Jetty doco on this.
So I have added the following to the jetty.conf
# ============================...
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Why are cgroups (blkio serviced bytes) and iotop producing diverging results
I work with lxc user space tools on ubuntu 14.04 and I want to perform some stress tests and benchmarking within a container. I know that free and htop are not working properly in a container.
I am ...
3
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1
answer
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Is it possible to configure the Linux kernel I/O scheduler for an NFS mount?
On a normal block device you can change the i/o scheduler like this:
# cat /sys/block/hda/queue/scheduler
noop anticipatory deadline [cfq]
# echo anticipatory > /sys/block/hda/queue/scheduler
# ...
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1
answer
427
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A testing framework for Linux server configuration management
We are a medium sized shop that uses Puppet for Linux configuration management. Since we are a small shop, it's difficult to deploy and maintain DTAP environment.
We normally perform manual testing ...
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1
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How do I force sftp user to start in their home directory
I am using RHEL6 and I set up an sftp server through sshd. Here is the relevant sshd config:
Match Group sftpusers
ChrootDirectory /sftp/%u
ForceCommand internal-sftp
X11Forwarding no
...
- 1,154
2
votes
1
answer
589
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SMI generation / detection in GRUB / real mode vs. in Linux
I'm trying to get an idea of the frequency and duration of SMI events on a Supermicro X10SAE C226 board (2.0a BIOS) with E3-1245v3 Haswell CPU.
The Intel BIOS Implementation Test Suite (BITS) SMI ...
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