Questions tagged [linux]
Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.
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Network Gateway Options for Small Office: Cisco 800 series router vs. Linux/*BSD (e.g. pfSense) on a white box vs. reflashed DD-WRT/Tomato/OpenWRT
Our existing network gateway's hardware has just failed (it was a repurposed desktop machine running Debian + Shorewall that we threw together), and we're looking to replace it. For now, we've fallen ...
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awk + perl + get two arguments in to awk syntax
please advice what wrong with my awk syntax and how to fix it ( this syntax is in my ksh script ) and I run my script on linux machine
my target is to get from the file.txt only the lines that ...
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Neverending screen.
My goal is to start bunch of processes from bash in screen but screen should not terminate after the process running in it ends or stops with error.
So im going to do someting like:
do a config file ...
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netstat reports ESTABLISHED connection even after I've pulled the cord
I'm experimenting with lost connections between my java application and my mysql server.
The application and the server are on two different machines and I'm pulling the physical cord between the ...
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Buffer-stuffing denial-of-service attack
I started seeing this odd sort of effect that resembles denial-of-service attack against a Linux server. The effect is that the network becomes at least partially unusable very much the same as what ...
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How to ban hardware interrupts with IRQBALANCE_BANNED_CPUS on Ubuntu?
I would like to ban interrupts from certain CPUs. I heard about the IRQBALANCE_BANNED_CPUS option. I see irqbalance is running in the background of my machine. Where do I go to edit and how do I ...
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Shared Block Device File System (iSCSI)
I wanted some advice on a file system to use on across 5-10 servers that have a shared block device (iSCSI), GlusterFS and LusterFS seem to be it, but they dont say anything about shared block device ...
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Debugging high inbound traffic
One of my development servers (CentOS 6) has suddenly seen a huge spike in inbound network traffic
It's slowing things down to a crawl, SSH is taking >10 seconds to log in and there is a delay when ...
user80776
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Can't log in locally, but SSH works
I can't log in to the console locally. After logging in, it flashes back to the login prompt. If given a wrong password, it will pause for a couple seconds then give the standard "Login incorrect" ...
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Determining TCP Congestion
How do I detect if I have TCP Congestion from looking at TCPDump data from a Linux box running a 2.6.x kernel ?
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How to Undo apt-get remove?
I know it is funny situation but i removed python with all associated programs from Ubuntu using sudo apt-get remove python?
Obviously i can install back python, but it will take me a lot of time to ...
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How to debug dropped SYN-ACK packets
I have 2 load balancers in front of 4 other server machines doing roughly a combined 5-6000 requests per second. I've noticed that every few minutes, one the load balancers gets a connection timeout ...
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Adding a new drive on a Linux database server
This is a general question to optimize performance, reliability, and consistency. I know that both of these methods work, I'm just wondering if there are (dis)advantages to one over the other.
...
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Admin 100's of VPS's
I have (so far) about 50 VPS's that I have to deploy and have my clients manage thought some sort of control panel.
Initially I thought I'd install ISPConfig 3 on each one of them and use their API ...
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unable to log in to Linux server with ssh
I have a server with real IP Addresses connected to my office network.
once I change the server IP address to a different IP (10.0.0.100) and connect my laptop to it
I'm unable to connect to it with ...
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Can I use iptables to limit port's outgoing bandwidth?
I want to limit my linux server port 8080 at speed 500KB/s, can I do this with iptables?
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How to clone a Linux server on EC2
Hi have a linux server on EC2 and I created a snapshot from that server, the the snapshot has been used to create an AMI, then I created an instance from the AMI. I always get a file system error, ...
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asterisk far end nat traversal not working
We use a obfuscation software to encrypt/mangle both SIP/RTP which sits before asterisk. What happens is sometimes we don't get any voice. after some "rtp set debug" we found out that when received ip ...
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What happens when I kill a command with ctrl+c?
Specifically, I ran a rm -R /my/dir by mistake on a ubuntu 10.04 machine.
When I realized the horror, within a few seconds, I quickly killed it with the Ctrl+C command. It now seems I haven't lost ...
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postfix and local delivery
I have postfix on my Ubuntu 12. My server has real domain name (ddd).
But I would like to use postfix for web scripts on my server to sending out emails.
My real domain name is connected with GMail. ...
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iptables command to add non-standard SSL port, 444
Below is my IP list output. What IP tables command should issue to enable the addition of tcp port 444, which I'm using for non-standard SSL. I tried "iptables -A INPUT -p tcp --dport 444 -j ACCEPT" ...
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use sed in shell script to replace IP Address in a file
I have a script that finds a string in a file replaces it with a new string.
$ sed -i 's/$old_string'/'$new_string'/g' $FILENAME
Now I need the condition to be a regular expression that also check ...
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How/What RC level to use to start a screen with Display attached.
Some times, after a reboot, some of my apps that have a GUI close. These apps provide web interface as well, but only if their gui potion is open.
If the unit is physically available to me, I can ...
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Linux user group configuration for Git bare repository
I'm using a Ubuntu box to host my bare Git repositories for developers to work off.
At the moment I'm creating a user account for each developer on the box because it doubles as a filestore and local ...
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is there a way to manage DNS without being a sysadmin?
I had a server at a linode, and they provided a great interface to manage DNS. I have my domain registered at verisign, and just pointed to ns.linode.com and went from there.
Now, I have a box at a ...
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iptables preroute localhost
I would like to forward all incoming traffic from a certain port to another one using iptables. The problem is that prerouting doesn't work for traffic from localhost. This topic suggests a solution:
...
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Squid Proxy - Hiding the proxy
I have setup squid proxy on an ubuntu server with DB authentication. However, whilst connected to the proxy, if I visit http://www.whatismyip.com/ it still shows my ACTUAL ip address. How can I ...
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What are Linux SCSI command timeouts and is the default suited for software raid?
My understanding of SCSI timeouts is that any read, write, flush and other commands have a limited time to complete. If exceeded, the command is aborted and an error is reported to the upper layer. ...
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Running multiple background Java processes on Linux
I have a jar file that runs continuously and acts on various events. I need to create multiple instances of this jar, passing parameters to it on start up, and have it continue to run between shell ...
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Central backup server?
We've got a bunch of Linux and Windows Servers that I'd like to do full-system backups of -- to a centralized Linux Server.
Ideally we'd have de-duping and versioning; but it's not required.
I haven'...
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Install Red Hat Enterprise Linux 5.5 on Proliant ML150 G2 server
I am investigating if I can install Red Hat Enterprise 5.5 on Proliant ML150 G2 server but I don't know if this configuration is possible.
Is this configuration possible?
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SVN info shows old Revision # as the Current Revision
I have an SVN repo. When I recently committed a change, the reflected current revision # is 620:
Transmitting file data ...
Committed revision 620.
However, if I then runsvn info I get the following:...
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identity and rectify port scanning activities on CentOS [duplicate]
Possible Duplicate:
My server's been hacked EMERGENCY
My Linux (CentOS 5.x) machine seem to have been attacked. Port scanning activities were traced to it. However, the ports (to be) scanned ...
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linux + generate new file with specific structure from text file what the best option
in my Linux machine I have the file orig-file.txt
this file include now 4 fields but they could be less or more ( this file generate by other application )
I need advice - what the best option to ...
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cp command, ignore unchanged files
Is there a way to do a cp but ignoring any files that may already exist at the destination that aren't any older then those files at source.
Basically I want to copy the contents of one disk to ...
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nl command + number each line in a text file only from the third line
I want to number each line in a text file on Linux/solaris by nl command
but only from the third line - is it possible ? and if yes please advice how ?
for example
line1
line2
1 line3
2 line4
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Remote Access from Windows to Ubuntu Server with mstsc.exe easy-going?
I installed for testing win server 2008 and its really easy to get remote access. Just enable RA with one click and then im able to get access with my win 7 with mstsc.exe - IF I would install a linux ...
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using chkconfig to run multiple copies of a service
im building a suse server. i have multiple copies of postgres running on it. i have the three instances running side by side just fine, the problem is when i try to get it to automatically start, i ...
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error while installing the libmemcached
I get this while installing libmemcached
root@server [/libmemcached]# make
make all-am
make[1]: Entering directory `/libmemcached'
if /bin/sh ./libtool --tag=CXX --mode=compile g++ -DHAVE_CONFIG_H -...
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Solaris + sort file according to date and time by sort command
I have along list that created in /var/tmp/file.txt from some script (in Solaris machine)
the following list have 4 fields
please advice how to sort the list according to the following TIMESTAMP ( by ...
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ENOEXEC on CIFS in SUSE
I am trying to execute a program on a CIFS mounted partition in SUSE 11.1. Whenever I try executing it, I get a "could not execute binary file" error. Using strace, I was able to determine that the ...
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How do you take a physical drive offline using HP P410i RAID card
How do you take a physical drive offline using HP P410i RAID card ?
Specifically in a RAID1 array I want to use hpacucli tool to take a physical drive offline then online to test if RAID1 array ...
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Nagios Host Downtime Scheduling
Ok, so I've spent a bunch of time on this and I can not seem to get it working in my environment.
I have a Nagios 3.3.1 server with NConf 1.3. All works well and I'm pretty happy.
However, I have a ...
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making one computers bash prompt match anothers
The computer who's prompt I'm trying to copy:
[root@CompanyName-LAMP-DEV:/current/path]$
We'll call that computer computer A.
The prompt my computer - computer B - currently has:
[root@ip-x-x-x-x /...
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Linux file ACL and secondary groups
The Problem:
CentOS does not seem to look at secondary groups when using ACL's on a folder or file
Scenario: CentOS 6 basic install, uses LDAP accounts to authenticate users. I am trying to setup ...
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which version of Apache to install on my Centos 5.x Linux
I see that there are two different releases in the Apache.org website.
one version is httpd_2.4.1 and another version is httpd_2.2.22 both are latest version.
any one have an idea?
Thanks!!
E.
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Rewrite a directory to / while keeping actual directory structure in tact?
My site exists www.site.com/forum I have no need for /forum but I do not want to go through the effort of changing everything. Is there a way I can get Apache to rewrite the URL so that it uses the ...
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EC2 instance always ask me to enter passphrase for the pem during connection
The pem file is generated by AWS console
I was able to connect using the EC2 remote web interface, using the same pem file
The permission of pem is 600 already
Error..
ssh -i ~/test.pem -v ubuntu@...
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O0o.oops() [console.c(83)]: Opening console failed and ssh_exchange_identification: Connection closed by remote host
During maintenance yesterday I did a mistake moving files and instead of mv ./* /destination-path, I typed mv /* /destination-path ... :( I stopped the process of moving in the middle and then moved ...
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ASA site-to-site IPSec vpn to linux ipsec-tools endpoints stops working after a random period of time
We swapped to ASA's over the weekend, and we replaced our VPN infrastructure which was previously based on openvpn and are now using IPSec between our ASA 5520's and our other sites that have linux (...
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