Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.

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7
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7answers
3k views

How can I automate clearing and resetting a Linux user's home directory to a default?

I'm helping to teach two Unix courses next week. Users will be granted an account on a RHEL 5 machine, during which time they'll add files to their /home folder, update their .bashrc and other ...
0
votes
0answers
7 views

HA Webserver cluster Architecture [on hold]

I'm getting interested in the webserver world which is a totally different area than the standard linux systems administration world (to me at least) . I've been reading a lot and watching tech talks ...
6
votes
3answers
1k views

mdadm: Which disk is being rebuilt?

I noticed my software RAID1 degraded, and wanted to figure out which of the two disks in the array is being rebuilt/re-synced since they both show as being up. I am hoping someone can shed some light ...
0
votes
5answers
778 views

best opensource firewall

We implemented Untangle opensource firewall on our network and interested to know various other firewalls with GUI interface. Can someone suggest which are the best opensource firewall implemented. I ...
-1
votes
1answer
48 views

Building router with one ethernet interface

Good day! I have 2 servers in datacenter and I want to use one of them as router for another instead of default gateway provided by DC. Both servers have one ethernet interface called 'eth0' with ...
0
votes
0answers
6 views

Stream training videos to remote offices

So I lead a team of engineers located across 3 timezones, and when we have a meeting we record it, so that it can reviewed at a later date. Currently we are just storing it on an apache server. If ...
0
votes
0answers
8 views

How to create an Operating System with buildroot? [on hold]

I would like to create an x86_64 Linux Operating system using buildroot. I have googled a lot, but I could not find a proper guide to create an Operating system iso file. Could you please help me to ...
0
votes
2answers
1k views

Spambot Infection Detection

My server has been blocked by CBL for participating in curtwail spambot. Initially we suspected that it was coming from a PC and not from the server, but the router is blocking all packets on 25 ...
1
vote
0answers
7 views

Configure management tool to auto-configure by reading config file

The use-case is as given below: The user has a Flat File in his Linux system. This file is a human readable/editable file which contains the configurations for all the needed components of his ...
0
votes
1answer
32 views

Nginx server_name redirect

I am doing an mobile page redirect for my website,it success, but unfortunately it stay at the same domain name, exmaple: when i go johnson.com by phone it should go to m.johnson.com(Yes, this is ...
0
votes
3answers
232 views

Is there a way to escape spaces in file names in vsftpd's config file?

I am generating user config files for vsftpd on Debian Linux. The config files are simple in nature, but I am running into one issue. Is there a way to escape a space in the file name(s) for the ...
1
vote
1answer
18 views

How can there ever be an OOM scenario on Linux (heuristics behind OOM killer)?

I am aware of the concept of virtual memory. And with demand paging (depending on vm.overcommit_memory) you are able to allocate more memory than available RAM. Unless you "touch" a page nothing ...
1
vote
1answer
23 views

CentOS 7 statically configured network adapter keeps getting DHCP address

This is driving me nuts. I have a CentOS 7 system. It is acting as DHCP for the network it is attached to, is running Cobbler and PXE, but it is not the gateway. It is the primary file server for ...
1
vote
2answers
21 views

How to manage versions and dependencies on a virtual machine

I am new here on serverfault so bear with me please. I am currently working with static web (angular2) and php deployment primarily on DigitalOcean and AWS using nginx and apache2. Until now debian ...
33
votes
5answers
10k views

Can you have more than one ~/.ssh/config file?

We have a bastion server that we use to connect to multiple hosts, and our .ssh/config has grown to over a thousand lines (we have hundreds of hosts that we connect to). This is beginning to get a ...
0
votes
1answer
5k views

ERROR with rpm_check_debug vs depsolve

Transaction Summary ========================================================================================================================================================== Install 9 ...
1
vote
0answers
18 views

HP ProLiant DL380 G5 Linux Install

I would like to let you know up front I am very much a beginner here so please bear with me. To start I purchased two HP ProLiant DL380 G5's for cheap because a company down the road went under. ...
6
votes
3answers
3k views

Sniff UNIX domain socket

I know that some process is writing to a certain unix domain socket (/var/run/asterisk/asterisk.ctl), but I do not known the pid of the sender. How can I find out who is writing to the socket? I have ...
0
votes
1answer
1k views

vpnc client ( open source ) that can connect to checkpoint gateway

I am searching for a long time a vpnc client ( open source ) that can connect to checkpoint gateway ( firewall ) Until now without any results I need vpn / vpnc client for Linux machine ( no matter ...
0
votes
2answers
88 views

How to make /mnt/resource readable/writable but other users in Azure Linux VM?

Right now /mnt/resource is owned by root and only root can read/write. How can I make this readable/writable by other users on the system? And this should be persistent (i.e. after system restart it ...
6
votes
4answers
3k views

Read only bind-mount?

I use mount -o bind to mount directories inside chroots, which works really well. The problem is that I'd like some of these bind-mounted directories to be read only in chroot. Is it possible? If not ...
0
votes
2answers
1k views

How to find max connections used by memcached?

In our LAMP application we have increased the max connection value for memcached to very high to avoid error for max connection we were having. Now we want to set appropriate value to max connections ...
2
votes
2answers
34 views

Showing the IP in the banner before login

I have a Linux machine and I want it to show the current IP in the banner that shows before the login prompt is displayed. How can I do that? I considered making a startup script that finds the IP in ...
2
votes
1answer
2k views

DJBDNS DNSCache configuration, svscan won't start

I've been wracking my brain the last few days trying to setup DJBDNS on my server. I haven't been having too much luck. I have been following the guide provided by the creator of DJBDNS: ...
10
votes
2answers
16k views

Writing to stdin of background process

I'm on an Ubuntu 10.04 box, and started a server in the background (myserver &) over ssh. It's been running fine, but I need a way to get at the server's stdin, as the only way to control the ...
1
vote
1answer
15 views

is online resize2fs ext4 close/reset all open files?

On my CentOS 6.x I did online ext4 filesystem resize using resize2fs. The only program running on this disk was sphinx search. I noticed that sphinx server had lots of: [Sun May 1 11:11:11.479 ...
0
votes
2answers
86 views
+100

Route all network traffic through an openvpn connection and also accepting incoming requests on the hosts' real IP-address

I am searching for a solution to route all traffic from a server through a VPN-client and still can handle incoming connections to the servers hosted services. All traffic to these services can bypass ...
1
vote
2answers
286 views

OpenSSH - how to require PublicKeyAuthentication *and* login/password authentication

I have an Internet facing server that I need to allow shared (non-administrative) access to. I want to allow access only if the users key is in an authorized_keys file, but I don't trust some of ...
0
votes
2answers
38 views

Common way to adminstrating ca-certificates on linux?

I have to administrate a bunch of linux machines (server and clients) with different distributions. We want to use docker in the future, so it may be, that there would be more different distris in the ...
0
votes
0answers
12 views

iptables, ufw, and psad - scanned UDP port alerts from router and devices on home network

I have a fresh install of Ubuntu 16.04. I configured iptables, ufw (with gufw), and psad using instructions from https://www.thefanclub.co.za/how-to/how-secure-ubuntu-1604-lts-server-part-1-basics and ...
1
vote
2answers
51 views

100 % inodes in root directory, how to free inodes?

df -i Filesystem-----Inodes-----Iused-----IFree-----IUse-----Mounted on dev/sda2-------732960-----727804-----5156-----100%---- / Only these 2 are having higest inodes, rest all are too low. what can ...
1
vote
0answers
17 views

Why do I have 70k instances of ck-get-x11-server-pid running?

I have a Ubuntu 14.04 server which currently has 69890 instances of ck-get-x11-server-pid running. The server is headless, but users can login to a using x2go. Why would there be so many instances of ...
0
votes
2answers
36 views

why does 'rsync --delete-before' delete files from target that still exist at the source?

I have a centOS 7.1 linux box with rsync 3.1.1. There are files there that I want to transfer to a FreeNAS 9.10 machine. For this I've set up an rsync daemon on freeNAS and transferring files works ...
1
vote
7answers
1k views

Secure file transfer in linux without SSH?

First thing i want to apologize if this question is silly or something...i just tried to research but it seems to be a bit hard to find exactly what i want in Google ! [or i'm not smart enough to find ...
3
votes
2answers
8k views

Cronjob run every two weeks, on Saturday, starting on this saturday [duplicate]

Today is Friday, October 3, 2014 3:58 AM I want to schedule a cronjob like that to run it at the following dates: Saturday, October 4, 2014 8:00 AM Saturday, October 18, 2014 8:00 AM Saturday, ...
1
vote
1answer
17 views

Sendmail dsn=5.0.0 Service unavailable when sending mails by PHP to yahoo

I got question regarding sendmail, I already searched for similar questions but couldn't find anything which was helpful to me. I am currently using a server (Debian with LAMP Stack) with sendmail, ...
0
votes
2answers
511 views

Setting up iptables filter to allow Git

Sorry I am new at this server stuff, so bare with me and if I'm missing any info let me know! I'm trying to setup my Ubuntu 14.04.2 LTS server to have a solid iptables firewall. Right now I think it ...
1
vote
1answer
40 views

Simulate massive network traffic [on hold]

We want to stress test our pfsense box with a massive amount of connections and traffic. Right now we are using iperf, but reaching a number of more than ~300 parallel connections the test clients ...
9
votes
3answers
16k views

How to stop/prevent SSH bruteforce

I'm very new to network administration, so please regard that I'm not that experienced yet. I have a Ubuntu root server with plesk panel. Yesterday my friends and I noticed that the quality of ...
0
votes
0answers
43 views

Running Apache2 in xenserver

I am trying to run my own squirrelmail email server. This involves the use of apache2, postfix, and squirrelmail. When I first boot up the server everything will work fine, but after about 1 - 2 ...
0
votes
2answers
1k views

monit fails to start apache

I'm running Apache, and trying to monitor it wiht Monit. The monitoring seems to work fine, but when Apache is down, Monit does not succeed to start it. Monit does detect that it's down, but the ...
0
votes
3answers
73 views

IP forwarding on Linux

I have three machines Source Machine Destination Machine - IP 10.20.30.40 Intermediate Machine - Host server1.test.com Source machine has SSH access to Intermediate machine and Intermediate machine ...
0
votes
2answers
4k views

How to disable local relay in postfix, for unauthenticated users?

I want to prevent my php scripts from sending mails through the MTA in localhost 25, without authentication. I have been told that the server, by default, trusts itself, and that's why I need no auth ...
-1
votes
0answers
11 views

How to centrally monitor multiple web servers and VPS uptime? [duplicate]

I have several VPS with different hosting providers running Linux (CentOS and Ubuntu) and FreeBSD. Several of them are self-managed. From time to time, there's server issue causing service ...
0
votes
2answers
25 views

Linux: where to store Java trusted CAs

I need an advice regarding the best practice of storing organisational CA on Linux servers for Java. Basically, JRE installation contains a list of trusted CAs in cacerts file, which is used by ...
2
votes
2answers
13k views

PPTP VPN Problem

I am using Debian OS with pptpd. My clients (both Windows and Mac) cannot complete the connection. The following shows in syslog: Jun 2 12:52:37 vpn pptpd[891]: MGR: Maximum of 6 connections ...
0
votes
0answers
9 views

What's a reproductable way to set up a Linux server for sending e-mails but no spam? [duplicate]

I've created a software that has to be installed onto a Linux server and from time to time it has to send a notification email. So, for people who want to use my software, I've created a bash script ...
0
votes
0answers
10 views

How to blacklist an IP range (subnet) on cphulk via terminal? [on hold]

I know how to blacklist a given ip with /scripts/cphulkdblacklist 192.168.0.1 But that's what I need to do... (not sure if any of these would work) /scripts/cphulkdblacklist 192.168.* .* ...
9
votes
10answers
9k views

How to determine if I'm logged in via SSH?

I'm currently setting up a fairly complex bash configuration which shall be used on multiple machines. I try to find out if it is possible to determine whether I'm logged in via SSH or on a local ...
0
votes
1answer
1k views

s3fs “could not determine how to establish security credentials”

I'm trying to use s3fs to mount an S3 bucket on to a standard AWS Amazon Linux AMI (with all the necessary dependencies installed). However when following this tutorial when I run: s3fs mybucketname ...