Ubuntu Linux is a Debian derivative that aims to bring Linux mainstream. Questions on this site should generally refer to Ubuntu Server. Note that http://askubuntu.com is specifically dedicated to Ubuntu questions.

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Running Multiple Publicly Accessible Web Servers on a Single IP Address

I have three separate web servers with three different internal IP addresses on a network with only one public IP address. Each web server has security restrictions such that I cannot just run all of ...
14
votes
1answer
11k views

Multiple php versions simultaneously on Ubuntu

I want to be able to run multiple php versions on my development box running Ubuntu 12.04. What I want to accomplish is that when I use localhost as domain a default is used (let's say php 5.3.17). ...
13
votes
3answers
39k views

Run nginx as a non-root user

I followed this process to installing nginx on my Ubuntu 10.04 Lucid Server http://library.linode.com/web-servers/nginx/installation/ubuntu-10.04-lucid I got lost after the point of creating an init ...
9
votes
2answers
12k views

Nginx Config: Front-End Reverse Proxy to Another Port

I have a small web server that serves requests on port 5010 rather than 80. I would like to use nginx as a front end proxy to receive requests on port 80 and then let those requests be handle by port ...
9
votes
2answers
18k views

SFTP fatal bad ownership or modes for chroot directory ubuntu 12.04

I just set up my SFTP server and it works fine when I use it from my first user account. I wanted to add a user which we will call 'magnarp'. At first I did like this in sshd_config: Subsystem sftp ...
9
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6answers
3k views

GUI on Ubuntu server?

I'm primarily a developer, but as part of this I'm running an Ubuntu server for a client where he has several small to medium sized websites. Although my main development environment has generally ...
8
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5answers
1k views

Setting up an Email Server on Ubuntu

What are some of the Dos and Don't to setting up an email server on Ubuntu? Are there any gotcha's?
8
votes
5answers
26k views

Disable usage of console-kit-daemon in Ubuntu

I administrate several Ubuntu 9.04 servers, and everytime I log in, I get the Landscape utility printout with server stats, etc. I really don't need this and it slows down my logins considerably. ...
7
votes
4answers
5k views

RAID 1+0 vs RAID 0+1

I went with some advice I was given from someone I know to go with a RAID setup for this server I ordered. The specs are below. I plan on using this server to host multiple sites in a PHP/MySQL ...
6
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2answers
4k views

How to determine which file/inode occupies a given sector

I received messages in /var/log/kern.log that indicate drive failure. The messages occured while copying my $HOME between drives (ext4 -> ext3): [ 5733.186033] sd 4:0:0:0: [sdb] Unhandled sense code [...
5
votes
2answers
3k views

Network authentication + roaming home directory - which technology should I look into using?

I'm looking into software which provides a user with a single identity across multiple computers. That is, a user should have the same permissions on each computer, and the user should have access to ...
5
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3answers
2k views

Setting up a postfix email server

When I set up an email server using postfix on ubuntu server, how do I make sure that it won't be an open relay??
5
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1answer
4k views

Ubuntu Linux - two interfaces, same subnet, different vlan - MAC/ARP issues

I'm attempting to setup a server that needs to have interfaces on the same IP subnet, but different VLANs: eth1.102 Link encap:Ethernet HWaddr 00:50:56:b1:00:0f inet addr:10.1.1.6 ...
5
votes
5answers
11k views

How do I know what processes are using the network?

Sometimes I can see heavy usage of network in my Gnome System Monitor. I wonder what process is downloading/uploading data. Is there any tool which can show me: what processes are using the Internet ...
5
votes
2answers
8k views

Low latency TCP settings on Ubuntu

There is a server for measurements running on Ubuntu in my lab . And there is C program, which receives data through TCP connection and should as soon as possible send a reply. Network latency when ...
4
votes
3answers
5k views

Using GlusterFS for simple replication

newbie question. I need to build this: /shared folder ~500GB of files, ~1MB each one. Two boxes (server1 and server2) connected by a 1Gbs LAN Every box needs to get r/w access to the files, so ...
4
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2answers
2k views

Remote server hangs, gets stuck. How to debug?

I have an vps running on VmWare ESX with Ubuntu 8.04 LTS. It has been running smoothly for the past 3 months, however recently we've notices two strange bugs. a. The server hangs, today was second ...
4
votes
2answers
3k views

Second ENI in AWS VPC is not accessible on Ubuntu instance

I'm just getting into VPC, trying to understand how everything works. So far the biggest hurdle I've run into is that any time I add a second Elastic NIC to a machine, that second IP is not accessible ...
4
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3answers
4k views

PHP 5.2x on Ubuntu 10.04 Lucid Lynx

It appears that Lucid Lynx comes with PHP 5.3. Is there a convenient way to downgrade to the latest 5.2x release?
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2answers
4k views

Linux (Ubuntu) run script upon USB mount

I have a Ubuntu server with a external USB hard drive. I basically just want to run a script whenever the hard drive is plugged in. What would be the optimal way to achieve this ?
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3answers
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how to completely disable ipv6 on Ubuntu 9.04

what i have done: /etc/modprobe.d/blacklist.conf blacklist net-pf-10 blacklist ipv6 /boot/grub/menu.lst title Ubuntu 9.04, kernel 2.6.28-15-server kernel /boot/vmlinuz-2.6.28-...
23
votes
9answers
13k views

How to view all ssl certificates in a bundle?

I have a certificate bundle .crt file. doing openssl x509 -in bundle.crt -text -noout only shows the root certificate. how do i see all the other certificates?
23
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5answers
62k views

Why should I enable IO APIC in VirtualBox?

What are the advantages of checking the "Enable IO APIC" option in VirtualBox? While I can't find any information on advantages when I google it, two disadvantages are clear. First, it can break ...
22
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5answers
6k views

A domain I've never heard of resolves to my website [duplicate]

I've discovered (via looking at mod_pagespeed cache entries) that a completely random domain I've never heard of before is resolving to my website. If I visit this domain, my website loads. The DNS ...
17
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4answers
37k views

How do I request a new IP address from my DHCP server using Ubuntu Server?

I know there is a simple command for this, but how do I tell my Ubuntu server instance to request a new IP address from the DHCP server on eth0?
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3answers
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what is sensible-mda and do i need it?

I'm running Ubuntu Intrepid, and have been seeing the following my logs: Aug 23 16:01:03 wp1 sm-mta[13700]: n7NFJIad013566: Warning: program /usr/sbin/sensible-mda unsafe: No such file or directory ...
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4answers
3k views

Is there an open source email client that will work with Exchange 2007?

Recently I've been playing around with Ubuntu 9.04 on one of my work systems. The only real bump in the road that keeps it from being being used as my main workstation is that I cannot find a ...
16
votes
3answers
41k views

Soft limit vs Hard limit?

Can anyone explain in layman's terms what the difference between soft and hard limit is? Should I set my soft and hard limit to be the same? Or should soft be significantly lower? Does the system ...
12
votes
5answers
7k views

Port Forwarding from Host to Guest with libvirt 0.8.3 Using KVM on Ubuntu

The host has a single external IP available, so I set my KVM guests up with NAT. How do I set up a port forwarding to forward some of the requests from the outside to the guests? I couldn't find ...
12
votes
11answers
8k views

Any way to run Linux as a Virtual Machine on top of Windows so can have best of both worlds?

Since Linux has a lot of useful tools, while Windows has a lot of apps (like Chrome), instead of buying another machine to run Linux, is there a way to run it as a Virtual Machine on the PC? The ...
10
votes
2answers
6k views

My linux server was hacked. How do I find out how and when it was done?

I have a home server running a desktop ubuntu distribution. I found this in my crontab * * * * * /home/username/ /.access.log/y2kupdate >/dev/null 2>&1 and when looking in that directory (...
9
votes
3answers
16k views

Allow scp/ssh for www-data user

I am on Amazon EC2 using Ubuntu 10.04.2 My web folder is owned by www-data so I want to be able to log into my server as www-data for ssh and scp. Thanks! Adding the line to my /etc/ssh/sshd_config ...
8
votes
7answers
7k views

Simple Mail System for Ubuntu?

What I'm looking for should be relatively easy. All I want to do is setup something VERY small for Ubuntu that will allow me to use the mail() function in PHP from my web server (/var/www/). I don't ...
8
votes
4answers
9k views

/bin/ls not found, even though it exists!

This is a server running ubuntu 8.04 server, any idea what's going on? # ls -bash: /bin/ls: No such file or directory # /bin/ls -bash: /bin/ls: No such file or directory # stat /bin/ls File: `/bin/...
7
votes
6answers
10k views

Unable to start rabbitmq-server on Ubuntu 12.04

I try to install rabbitmq-server on ubuntu-server 12.04 but failed. Then I add the apt source list following the guide in http://www.rabbitmq.com/install-debian.html But reinstall still have the ...
7
votes
2answers
4k views

Can't get SASL auxprop/sasldb working with postfix/Ubuntu 12.04

I have an Ubuntu 8.04LTS system running Postfix 2.5.1. On that system SMTP AUTH runs fine. The contents of /etc/postfix/sasl/smtpd.conf are: pwcheck_method: auxprop auxprop_plugin: sasldb mech_list: ...
6
votes
4answers
1k views

Easy way to convert custom 32-bit AMI into 64-bit one?

I have customised (EBS-backed) AMI for running a demo version of an application of ours. (The AMI contains Ubuntu 11.04 with a Tomcat & MySQL setup for the app itself, and Jenkins for easy one-...
6
votes
5answers
2k views

Disable/Remove Apt(-get)

Is there anyway to disable/remove apt-get on a debian based server. I'd prefer to use aptitude, and don't want the other users to be installing packages with apt-get, to avoid package/database issues.
6
votes
1answer
9k views

Ubuntu: Network driver reset to eth0?

I've been trying to get my Ubuntu Server VM running through VirtualBox. I ended up trying several network interfaces because of some networking issues and finally got it working. However, I noticed ...
5
votes
4answers
1k views

Effectively handling 2+ million files

I have a file based DB that has about 2M files stored in 3 levels of subdirectories. 2/2/6253 2/2/6252 ... File a vary from 30 bytes to 60 KB. Whole DB is Read Only. DB is about 125 Gigabytes big. ...
4
votes
5answers
22k views

possible SYN flooding on port 80. Sending cookies

I recently had a server downtime. I looked everywhere and the only thing I found in my log files is: Feb 17 18:58:04 localhost kernel: possible SYN flooding on port 80. Sending cookies. Feb 17 18:59:...
4
votes
2answers
2k views

Port forwarding to virtual machine

I'm running an http(zope) server on Ubuntu 8.04 server, in a Virtualbox machine, on an Ubuntu 9.04 box. The guest system accesses network over NAT. How can I forward the host machine's port 80 to the ...
4
votes
4answers
7k views

How Ubuntu cloud version enforces the “no root login” over ssh?

I'm looking to tweak ubuntu cloud version default setup where is denies root login. Attempting to connect to such machine yields: maxim@maxim-desktop:~/workspace/integration/deployengine$ ssh root@...
3
votes
1answer
2k views

Default permission for newly-created files/folders using ACLs not respected by commands like “unzip”

I am having trouble with setting up a system for multiple users accessing the same set of files. I've read tuts and docs around and played with ACLs but haven't succeeded yet. MY SCENARIO: Have ...
3
votes
5answers
15k views

Huge amounts of “multiply-claimed blocks” during fsck

The basic question: How long should fsck take to fix a 100GB (17 million block) file with multiply-claimed blocks? The long version of the question: After a UPS failure, I am faced with an Ubuntu ...
2
votes
2answers
6k views

Permanently adding source policy routing rules

Somebody answered my earlier question by describing how to create a new routing table with source policy routing: echo 13 eth3 >> /etc/iproute2/rt_tables ip route add default via 10.20.0.1 ...
2
votes
1answer
14k views

Connect to WEP Wireless Network by command line on Ubuntu

I am a newbie to both network and Linux. I am now trying to connect to a WEP wireless network by command line on my Ubuntu 8.10, because the Network Manager does not support 64 bit WEP. (1) I ...
2
votes
2answers
6k views

Is there any bad thing happens if I change /etc/ldap/slapd.d/cn=config.ldif manually?

Since 2.3, OpenLDAP uses a configuration engine called slapd-config. They said that use it make all LDAP configuration can be changed on fly. This is the header of /etc/ldap/slapd.d/cn=config.ldif: #...
2
votes
3answers
7k views

Multiple UCARP VIPs on single Interface with Debian/Ubuntu

The example ucarp config for a virtual IP for Debian/Ubuntu is in /usr/share/doc/ucarp/README.Debian and is as follows: The recommended method for configuring ucarp is via /etc/network/interfaces. ...
2
votes
3answers
6k views

Tips to backup ubuntu server

I have a Ubuntu server hosting a PHP5 / MySQL webapp. I also have another server (offsite) with a directory just for backups of my webapp server. Currently, I have a simple cron job which performs ...