Newest ubuntu Questions

Q&A for system and network administrators

Deleted bash, how do I recover?

I deleted /bin/bash. I had terminal open, but it auto-closed later. I am a normal user in sudo group. What do I do? I'm panicked. Can I change file permission of /etc/passwd with Python / Perl and ...

Assign public IP address to virtual machine in Ubuntu 16.04 [closed]

On Ubuntu 16.04 server (Host) I have installed VirtualBox 5.1. I want to assign additional public IP to Guest ( Ubuntu 16.04 ). From information so far i found i need to use bridged interface and ...

DNS in ubuntu server 16.04 can't ping google but its IP

I just installed Ubuntu Server 16.04 on VMware (with bridge network with a static IP, following this tutorial) and can't resolve domain names. When trying to ping google.com, it returns ping: ...

Monit crashing on DigitalOcean 16.04

I have a Rails app running on DigitalOcean, Ubuntu 16.04. Sometimes one of its Puma processes spikes CPU for a long time, affecting performance. The fix is to kill it, this does the trick (at least ...

Locked out of my Ubuntu server

Everytime I try to log in (SSH) to my Ubuntu 14.04 server (DigitalOcean) it opens Letsencrypts certbot and asks me to choose a domain to install SSL on (already have it activated). But after that, it ...

How to stop apache2 on ubuntu - no process visible

I just installed ubuntu 16.04 and apache2. The default config page shows up even if I stop apache2. This is absolutly strange as there is no process httpd. The server keeps serving the default file ...

How do I access webserver which is running inside a docker which itself is inside a virtualbox vm? [migrated]

So my set up is a virtualbox ubuntu 16.10 vm which runs on a MAC host. Now inside the vm I have a couple of docker containers among which one runs a nginx webserver. Now I am running the VM on a host ...

How to deal with suspicious sudo user? [duplicate]

I am running Ubuntu 14.04 server with ISPConfig installed and etc. Latest I saw a suspicious home directory named ub. It has some encrypted files in it. Also I found /run/shm/ecryptfs-ub-Private is ...

Why is fail2ban finding but not banning

I noticed something strange on my Ubuntu Xenial server. It has SSH on the default port and it has fail2ban. Fail2ban is detecting brute force attempts on the server and are logged accordingly: 2017-...

How to temporarily run a secondary SSH server on a separate port

How do you run an SSH daemon on a different port other than the standard 22? I screwed up something with my SSH configuration on a cloud VM, so that now SSH always prompts me for a password. My early ...

Same domain emails are bouncing back others are working fine

I have moved recently my website to a VPS everything working well except for the email. Emails are delivering well on any domain other than the domain where website is hosted. E.g. emails are sent ...

SSH Jump Host WITHOUT Agent Forwarding

Although a simple question, I have searched for days without success. M = My machine J = Jump Host S = Server Jump Host has my public key on authorized_keys. Server has J's public key on ...

Gtk-WARNING: **: C\cannot open display: error running Brsckets on server

I deployed my vps server using Ubuntu 16.04 LTS Server. Then I installed the Brackets editor but after running brackets on the terminal I get this error, Gtk-WARNING: **: C\cannot open display: What ...

The arp-scan tool found machine but i can't ping [closed]

I have two VPS that i buyed from one corporation, OS of two VPS is ubuntu and when i ran arp-scan -l on one of the both machine and i can see IP of other machine, but i havn't any type of access to ...

Apt-Preferences doesn't accept package name

I have two repositories with one package "libtidy-dev": $ apt-cache policy libtidy-dev libtidy-dev: Installed: 20091223cvs-1.2ubuntu1.1 Candidate: 1:5.2.0-1+deb.sury.org~trusty+1 Фиксатор ...

Ubuntu server ext4 hitting 65000 subdirectory limit

I have a Ubuntu 14.04 server that is failing to create a new directory beyond the 65,000 directory. I have run a tune2fs -l and can see that the dir_nlink flag is set. Does anyone know what else can ...

Uptime for individual service

I am running multiple unicorn processes on my production server. Now I want to check the individual service uptime of my services. For instance if any unicorn process restart automatically, it should ...

Can't paste or type Japanese (or non-Latin characters) on Putty

I work with Japanese characters on Putty, and whenever I see question marks on Putty, I change the locale by typing export LANG="en_US.UTF8" Once I have done that the characters are shown on Putty ...

ldapmodify can't contact LDAP server for cn=config

I've been pulling my hair out for 3 days now trying to configure ldap. I first tried installing from source but then reinstalled using apt-get, which caused some migration errors, but I believe those ...

Building deb files for both Debian and Ubuntu [on hold]

While the tools are the same, the sections and distribution names are notably different between Ubuntu & Debian (and presumably other Debian-based distros). For example, a Lua library's debian/...

Ubuntu VM (VMWare) cannot connect to internet via VLAN

I've been given access to a university hosted cloud based VMWare virtual machine (vSphere). So far, I've been able to install Ubuntu (16.04) on the VM, but am hitting a wall in regards to connecting ...

postgresql track counts and autovacuum is not working

In the startup log entries indicate the autovacuum not working. I query the pg_stat_user_tables table and the last_vacuum and last_autovacuum columns are empty in spite of the vacuum query I ran just ...

How to add a local user to a remote group? ubuntu

I want to give a local user group access for a group on a remote cluster. I have ssh access from the machine to the group machine and want to know if there's a way to do this?

Ubuntu Running KVM with 3 NICs Setup

I am currently trying to setup a KVM server with two OS (pfsense & Ubuntu Server) on an Ubuntu server with three NICs (enp2s0, enp1s0, & enp3s5). This is the concept I'm trying to do: http://...

Apache subdomains go to main website

I am running an a vps on Ubuntu 16.10 and i have my main website site in this question it will be called (website.com) while on the other hand i have another webmail server (mail.website.com) which ...

Strange disc full error on Ubuntu - reboot clears the disc?

Every now and then, my Ubuntu server running PHP+mySQL server slows down until ultimately hangs, possibly because the disc is full. Here is what it shows right now: root@Ubuntu-1204-precise-64-...

Configure email for incorrect sudo password

I can't find any information on mail_badpass specified in /etc/sudoers and whether this is configurable. I'd like to make the emails a bit more readable and hopefully add more information in there ...

VSFTPD access of all user home direcrory?

How do you setup vsftpd so that the whole user's home directory and subdirectories are accesible not just the expected ftp directory in ubuntu 16.04 LTS server?

How to monitor linux server running virtual machines while Overcommitting? [duplicate]

In KVM, I am overcommitting CPU resource. I read, In KVM I can overcommit CPU upto 5 times. After overcommit,top command always show 100 %. I also used telegraf, nagios. How to monitor my machine's ...

Ubuntu root drive running out of space, I can't find source through du or lsof

The root drive on an Ubuntu 15.10 machine is nearly out of space, but I can't find the source. The drive that's running out of space is sdb2, 313M of 51G available. The filesystem is ext4. Here is ...

Restore VM from Base VMDK and snapshots created by Virtualbox on a headless ubuntu Server [migrated]

I wanted to resize an 80GB vmdk on an ubuntu server. I used VBoxManage clonehd /path/to/file.vmdk" --format vdi VBoxManage modifyhd "/path/to/file.vdi" --resize 256000 VBoxManage clonehd "/path/to/...

Where is the user's home directory that was created using adduser command in Ubuntu Server 16.04 LTS?

Where is the user's home directory that was created using adduser command in Ubuntu Server 16.04 LTS? Or I need to create it itself?

Config Error in HAproxy

I'm having an HAproxy as a loadbalancer on top of 2 backend servers. I installed the SSL certificate and this is my config which gives me tons of errors when reloading HAproxy. Please help! This is ...

Connection to a VPN with L2TP over IPsec [closed]

I am using elementaryOS Loki (based on Ubuntu 16.04) and I am trying to connect to the Windows network. Credentials I've been provided with are IP address (gateway) PSK (12 digit number) my login ...

Ubuntu wireless AccessPoint. How to measure data consumption for each connected IP

I need to mesure a web site data consumption. My plan is to use a Ubuntu PC as an wireless AccessPoint and use the Ethernet port as a gateway to the internet. On the Ubuntu, allow just the ...

Postfix External SMTP Authentication - Wrong login user?

I am trying leverage Postfix as an SMTP relayer on a Raspberry Pi to allow other systems on my network to email outbound system messages. It appears there are two problems, (1) it's not authenticating ...

apt-get purge removing seemingly unrelated packages

I somehow managed to remove the /var/run/saslauthd directory while installing authentication for Postfix, so I was trying to apt-get purge and then reinstall the various saslauthd packages in order to ...

Ubuntu 16.04 - frozen mdadm array

I had a working RAID5 array consisting of 6 4TB disks. Smartd reported that one of the disks started failing. I decided to do several things in one operation: 1) remove the failing disk 2) add new one ...

Error authenticating via SSH

One of our clients is attempting to start an SFTP session on our file transfer server. When they try to authenticate we see these errors in the auth.log. Jan 16 11:24:34 ft sshd[6898]: error: kex ...

docker npm ERR! install Couldn't read dependencies

While trying Docker Tutorial https://prakhar.me/docker-curriculum/#dockerrun getting error while running root@ip-172-31-22-20:~/docker-curriculum# docker build -t ashishkarpe/foodtrucks-web . root@ip-...

OpenVPN for certain IPs, eth0 for everything else

Summary: I'd like to connect to my VPN and have access to certain servers, but for all other traffic I'd like to use my regular networking. I've setup an OpenVPN server on my VPS, my server.conf file ...

Apache2: Are there any Reasons to NOT use Virtual Hosts?

this is more of a general question. I am experimenting with virtual servers and just configured a virtual host on Apache2 on a Ubuntu 16.04 server. I am just wondering, if there is ever a reason to ...

ntopng update error on ubuntu 16.04 LTS

An attempting update of ntopng on ubuntu 16.04 LTS resulted in this annoying error during 'apt-get install ntopng' ( run as root ) Executing /lib/systemd/systemd-sysv-install enable ntopng Failed to ...

ldap_sasl_bind(SIMPLE): Can't contact LDAP server (-1) error on Ubuntu but works on Centos

I am running Openldap as a docker container on Ubuntu Server 16.04 LTS. I get the following error when I do ldapsearch. The same command works fine on Centos OS. Could you please provide any ...

Protect my database password from developers

We have an application that uses a database at my workplace. Currently, it's using a username password to authenticate (though we could use trusted IPs connections). We don't want to use trust because ...

Ubuntu memory consumption

I've got the following output of the free -m command screenshot So as far as I understand, 6501MB is available for using. The problem is that I have a cron job executing some SQL and I've noticed ...

Securing a simple Linux server that holds a MySQL database?

A beginner question, but I've looked through many questions on this site and haven't found a simple, straightforward answer: I'm setting up a Linux server running Ubuntu to store a MySQL database. ...

mysql-server socket malfunction - Can't connect to local MySQL server through socket

os: ubuntu 14~ so I got Such errors $ sudo apt-get install mysql-server Czytanie list pakietów... Gotowe Budowanie drzewa zależności Odczyt informacji o stanie... Gotowe mysql-server is already ...

Unable to connect to Linux git Repo from Windows machine

So recently I've been trying to set up a Git server to manage personal projects and work. I created a bare Git repo on a spare laptop running Ubuntu and I installed Git Bash on my Windows machine. ...

How do I create a bridge between two virtualbox VMs? CentOS and Ubuntu [closed]

My main OS upon which virtualbox is installed is a *nix laptop. On virtualbox,I have two virtual machines, one is CentOS, the other is a Ubuntu box. I have created with brctl a bridge on CentOS called ...
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