RaspberryPi3B: Difference between revisions

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====Operation====
====Operation====
* [[JBoss#Logging_Configuration|logging]]
* [[JBoss#Logging_Configuration|logging]] in
  cd /wildfly/wildfly-19.1.0.Final/standalone/log
  cd /wildfly/wildfly-19.1.0.Final/standalone/log
* check server status
* check server status

Latest revision as of 10:33, 17 November 2025

Specification[edit]

  • package bought at amazon
  • Quad Core 1.2GHz Broadcom BCM2837 64bit CPU
  • 1GB RAM
  • BCM43438 wireless LAN and Bluetooth Low Energy (BLE) on board
  • 40-pin extended GPIO
  • 4 USB 2 ports
  • 4 Pole stereo output and composite video port
  • Full size HDMI
  • CSI camera port for connecting a Raspberry Pi camera
  • DSI display port for connecting a Raspberry Pi touchscreen display
  • Micro SD port for loading your operating system and storing data
  • Upgraded switched Micro USB power source up to 2.5A
  • 16GB Micro SD card

OS-Version[edit]

cat /etc/os-release // lists version 8
// kernel
uname -a // lists Linux raspberrypi 4.9.35...

Configuration[edit]

LAN[edit]

  • 192.168.178.35 for LAN

WLAN and Bluetooth switch off[edit]

  • old WLAN IP was 192.168.178.34
  • copy /boot/config.txt to /boot/config_2019-08-18.txt
  • add lines below to /boot/config.txt
# added by UH 2019-08-18 for disabling WLAN and Bluetooth
dtoverlay=pi3-disable-wifi
dtoverlay=pi3-disable-bt
  • reboot after change first time

Shared Public Directory[edit]

SSH[edit]

  • configuration is in /etc/ssh/sshd_config
  • all logins are documented in /var/log/auth.log
// the following entries are created by the local cron job and not critical
Aug 13 08:09:02 raspberrypi CRON[29805]: pam_unix(cron:session): session opened for user root by (uid=0)
Aug 13 08:09:02 raspberrypi CRON[29805]: pam_unix(cron:session): session closed for user root
  • SSH credentials (e.g. for WinSCP or Putty) for user=pi pwd=Halloo0@1 (old raspberry)
  • enable SSH access for root with pwd Halloo0@1 by
sudo su
passwd Halloo0@1
// edit /etc/ssh/sshd_config
// decommend PermitRootLogin without-password
// add PermitRootLogin yes
sudo service ssh restart
  • to just enable root for ssh
copy /etc/ssh/sshd_config to /etc/ssh/sshd_config_2019-08-18
add to ssh_config
   # added by UH 2019-18-08 10:05
   AllowUsers root
restart service by 
   sudo service ssh restart
  • cmd line access via fritzbox by
ssh root@uweheuer.spdns.de -p 54444
  • or use WinSCP

SD Card[edit]

  • SD Card is file /dev/mmcblk0 and mmcblk0p[1-7] are the partitions, see them
fdisk /dev/mmcblk0
p
q

Timezone[edit]

set to Berlin by: 

sudo timedatectl set-timezone Europe/Berlin

check with 

timedatectl

USB stick 1[edit]

  • pluged-in 64GB USB stick -> USB stick is sda1 (see lsblk)
  • windows partition table changed to Linux according to here
  • format USB stick to ext4 filesystem by
umount /dev/sda1
mkfs.ext4 /dev/sda1 -L USBSTICK
  • mount the USB stick by
cd /media
mkdir usbstick
mount /dev/sda1 /media/usbstick
  • make the mount permanent by
nano -Bw /etc/fstab
add line /dev/sda1 /media/usbdisk auto defaults,user 0 1

USB stick 2[edit]

  • pluged-in 128GB USB stick for backup of raspberry -> USB stick device is sdb, partition is sdb1 (see output of tail -f /var/log/messages)
  • the stick is formatted with FAT filesystem and is changed to ext4 by:
fdisk /dev/sdb
d
n + p
w
reboot
mkfs.ext4 /dev/sdb1 -L USBSTICK2
  • mount it
cd /media
mkdir usbstick2
mount /dev/sda1 /media/usbstick2
  • and for mounting it permanently add the following line /etc/fstab
/dev/sdb1 /media/usbstick2 auto defaults,user 0 1

Fritz NAS[edit]

  • mount the USB disk of the Fritz.Box
cd /media
mkdir fritzNAS

User[edit]

  • pi <Lr><STANDARD><Lr>

Software[edit]

Apache[edit]

Installation[edit]

  • verion 2.4 installed by
sudo apt-get install apache2
chmod 777 /var/www/html
  • to setup Apache as reverse proxy for Wildfly
sudo a2enmod proxy_ajp
  • creates proxy.conf, proxy.load and proxy_ajp.load in /etc/apache2/mods-enabled

Configuration[edit]

Site Configuration[edit]
  • /etc/apache2/sites-enabled/* are links to /etc/apache2/sites-available
  • for forwarding to Raspberry 4B in 000-default-le-ssl.conf
ProxyPass /fwdtest http://192.168.178.72
ProxyPassReverse /fwdtest http://192.168.178.72
Logging[edit]
  • see /var/log/apache2

Operation[edit]

  • restart
sudo /etc/init.d/apache2 restart or
service apache2 restart
  • find out version
apache2ctl -v // -> Apache 2.4
  • stop service
sudo service apache2 stop
  • log goes to
/var/log/apache2

Backup by RaspiBackup[edit]

Installation[edit]

  • installation according to here as user root
curl -sSLO https://www.linux-tips-and-tricks.de/raspiBackupInstall.sh && sudo bash raspiBackupInstall.sh
EN
N (normal mode)
RSYNC (backup type)
5 (number of backups)
Y (verbose message)

installs raspiBackup.sh and raspiBackupInstall.sh to /usr/local/bin and raspiBackup.conf to /usr/local/etc.

  • changed in /usr/local/etc/raspiBackup.conf to
DEFAULT_BACKUPPATH="/media/usbstick2/raspibackup"

Operation[edit]

  • open termminal
  • call backup by
/usr/local/bin# ./raspiBackup.sh -a : -o : -m detailed -P
  • map HomePC backup directory as described in here
  • copy latest backup to ../backup/raspberry/raspibackup/ by
/media/usbstick2/raspibackup/raspberrypi# cp -r raspberrypi-rsync-backup-<DATETIME>/ /media/ubunturoot/backup/raspberry/raspberrybackup/

Mediawiki[edit]

  • download mediawiki-1.25.1.tar.gz and copy it to /tmp
  • extract it by
tar -xzf mediawiki-1.25.1.tar.gz
  • rename directory mediawiki-1.25.1 to mediawiki by
mv mediawiki-1.25.1 mediawiki
  • move directory to the html directory by
 mv /tmp/mediawiki /var/www/html/mediawiki

$wgGroupPermissions['*']['read'] = false;
$wgGroupPermissions['*']['edit'] = false;
$wgGroupPermissions['*']['createaccount'] = false;
  • install ImageMagick for picture rendering by
sudo apt-get update
sudo apt-get install imagemagick
  • copy C:\Uwes\Programme\xampp\htdocs\mediawiki-1.16.0\images to /var/www/html/mediawiki/images
  • set images folder permissions right by
sudo chown -R www-data:www-data images/
sudo chmod -R 755 images/
  • prabably forget to describe DB copy from EON laptop to Raspberry

Backup[edit]

DB Backup[edit]
  • start xampp on laptop and start Apache and MySQL (works also on ZBook)
  • call (database mediawiki_raspberry3b to be there)
C:\Uwes\owncloud\batches\Raspberry3BMediawikiToLocalhost.bat // will update DB mediawiki_raspberry3b and document date in C:\temp text file

mysqldump --single-transaction -h localhost -u root -p  mediawiki > /media/ubunturoot/backup/raspberry/mediawiki/mediawiki_<YYYY-MM-DD>.txt
Enter password:
Directory Backup[edit]
  • on Raspberry
    • to Ubuntu (if it is switched on)
tar zcvhf /media/ubunturoot/backup/raspberry/mediawiki/mediawiki_<YYYY-MM-DD>.tgz /var/www/html/mediawiki
    • to local disc
tar zcvhf /backup/mediawiki/mediawiki_<YYYY-MM-DD>.tgz /var/www/html/mediawiki
tar zcvhf /backup/mediawiki/mediawiki_2022-06-29.tgz /var/www/html/mediawiki
      • copy it to Raspberry 4 /home/uwe/backup/Raspberry3B/MediaWiki via WinSCP
      • copy tgz file to external discs
      • copy tgz file to C:\Uwes\owncloud\backups\raspberry3B\Mediawiki via WinSCP

Upgrade from 1.25 to 1.33[edit]

  • install version 1.33
    • download the latest release (1.33) from here to laptop and copy it to raspberry /tmp directory
    • extract gz file in /tmp by
tar -xvzf mediawiki-1.33.0.tar.gz
    • move extracted directory to /var/www/html
mv mediawiki-1.33.0/ /var/www/html/
    • delete downloaded gz-file
    • copy images from 1.25 installation
 cp -a /backup/2019-08-27_mediawiki/images/* /var/www/html/mediawiki/images/
    • copy LocalSettings.php from 1.25 installation
cp ../mediawiki/LocalSettings.php .
    • edit LocalSettings.php (because of errors of the update script
      • decomment wfLoadSkin except Vector
      • decomment ConfirmEdit extension
    • disable PHP5 and enable PHP7.2
    • run the update script by
cd maintenance
php update.php

Install Msupload extension to enable Drag & Drop[edit]

Install MS Upload Extension[edit]

  • download and follow instructions from here

MySQL[edit]

  • install by
sudo apt-get install mysql-server php5-mysql mysql-client
root root
  • decomment in /etc/mysql/my.cnf
#bind-address		= 127.0.0.1
  • login with local client
mysql -u root -p

Backup[edit]

mysqldump --all-databases --single-transaction -h localhost -u root -p > /media/ubunturoot/backup/raspberry/mysql/DB_<YYYY-MM-DD>.txt

OwnCloud[edit]

Settings[edit]

Operation[edit]

  • make occ executable
root@raspberrypi:/var/www/html/owncloud# sudo chmod +x occ
  • test occ
root@raspberrypi:/var/www/html/owncloud# sudo -u www-data ./occ
  • scan filesystem and update DB
root@raspberrypi:/var/www/html/owncloud# sudo -u www-data ./occ files:scan --all

Installation[edit]

ownCloud installed according to here: 

apt-get install apache2 php5 php5-gd php-xml-parser php5-intl
apt-get install php5-sqlite php5-mysql smbclient curl libcurl3 php5-curl
usermod -a -G www-data www-data
  • download owncloud-10.0.3.tar.bz2
cd /var/www/html
tar xfj /home/pi/owncloud-10.0.2.tar.bz2
chown -R www-data:www-data /var/www/html
service apache2 restart
  • call <IP>/owncloud, admin user uwe.heuer@gmail.com Halloo0@1, DB root root owncloud localhost:3306
  • change data directory according to here by
mkdir /media/usbstick/owncloud/data
chown -R www-data:www-data /media/usbstick/owncloud/data
apachectl -k stop
rsync -avz /var/www/html/owncloud/data /media/usbstick/owncloud/
mv data data_obsolete
ln -s /media/usbstick/owncloud/data/ /var/www/html/owncloud/data
apachectl -k graceful
  • to make owncloud accessible via uweheuer domain added to /var/www/html/owncloud/config/config.php in trusted domains
 'trusted_domains' => 
 array (
   0 => '192.168.178.35',
   1 => 'uweheuer.spdns.de',
 )
  • to make it accessible only via SSL see '000-default.conf' and '000-default-le-ssl.conf' in /etc/apache2/sites-enabled/
  • to correct inconsistent database and filesystem
:/var/www/html/owncloud# sudo -u www-data php occ files:scan --all

Contacts[edit]

Calendar[edit]

Upgrade[edit]

  • user (right top corner) -> settings
  • admin area (left area) -> General -> Scroll down to Updater
  • install apps again

Backup[edit]

Backup Files[edit]
  • create /backup/BackupOwncloudFiles.sh with
    • cd /media/usbstick/owncloud/data/uwe.heuer@gmail.com/files
    • zip -rFS -P "<STANDARD>" /media/usbstick/backup/owncloud/owncloud_backup.zip .
  • zipping every night by sudo crontab -e
  • file will be fetched from Raspberry 4 and copied to Google drive (see here)
config directory[edit]
DB backup[edit]

created /media/ubunturoot permanently

  • start Ubuntu HomePC (via fritz.box or WOL)
  • login (as root) to Raspberry e.g. by Putty from Windows or Ubuntu
  • mount directory for backup by
sudo mount -t cifs -o username=uwe //192.168.178.202/shareroot /media/ubunturoot/
<ROOT_PWD>
  • change to Owncloud directory by
cd /var/www/html/owncloud/
  • backup DB by
mysqldump --single-transaction -h localhost -u root -p  owncloud > /media/ubunturoot/backup/raspberry/owncloud/owncloud_<YYYY-MM-DD>.txt
Enter password:
  • unmount directory by
umount /media/ubunturoot
Data Backup[edit]

PHP[edit]

PHP5[edit]

  • installed via OwnCloud installation. Is is not clear which ini-file is used:
./etc/php5/cli/php.ini
./etc/php5/apache2/php.ini // this one is used according phpinfo()
  • increased max file upload size for Wordpress by setting
upload_max_filesize = 4M // before 2M
service apache2 restart

PHP7.2[edit]

  • installation according to here
sudo apt update
sudo apt install php7.2
sudo apt install php7.2 php7.2-cli php7.2-cgi php7.2-common php7.2-curl php7.2-gd php7.2-json php7.2-mbstring php7.2-mysql php7.2-opcache php7.2-readline php7.2-xml libapache2-mod-php7.2
  • and in order to make Owncloud work with 7.2
apt-get install php7.2-intl
apt-get install php7.2-zip
service apache2 restart

apt-get install php7.2-bcmath
service apache2 restart
  • ini-files:
./etc/php/7.2/cli/php.ini
./etc/php/7.2/apache2/php.ini // this one is used according phpinfo()
  • switch to PHP7.2 (PHP5 remains installed)
a2dismod php5
a2enmod php7.2
service apache2 restart

PHPMyAdmin[edit]

  • installed by
apt-get install phpmyadmin
root root
  • add to /etc/apache2/apache2.conf at the end (marked by UH)
Include /etc/phpmyadmin/apache.conf
  • changed URL in /etc/phpmyadmin/apache.conf by
Alias /phpxmyadmin /usr/share/phpmyadmin
  • restart apache

SSL[edit]

Obsolete installation via Backports Packages[edit]

  • edit /etc/apt/sources.list and add
deb http://ftp.debian.org/debian jessie-backports main
  • backports are recompiled packages from testing and unstable in a stable environment so that they will run without new libraries
  • update
apt-get update
  • install via Certbot, a script to install and update Let´s Encrypt SSL-certificats
sudo apt-get install python-certbot-apache
sudo apt-get install certbot -t jessie-backports
sudo certbot --apache
uweheuer.goip.de uwe.heuer@gmail.com
  • creates among others /etc/letsencrypt

Upgrade Cerbot from Homepage[edit]

  • goto Certbot Homepage and select 'Apache' and 'Debian 8 (jessie)' and follow instructions
sudo apt-get remove certbot
wget https://dl.eff.org/certbot-auto
sudo mv certbot-auto /usr/local/bin/certbot-auto
sudo chown root /usr/local/bin/certbot-auto
sudo chmod 0755 /usr/local/bin/certbot-auto
  • certbot-auto accepts the same flags as certbot
  • decommented the backports entry in /etc/apt/sources.list
sudo apt-get update
  • then continue with Certbot configuration
sudo /usr/local/bin/certbot-auto --apache -d uweheuer.spdns.de
sudo /usr/local/bin/certbot-auto -d bbx0axbhewglhzf4.myfritz.net
sudo /usr/local/bin/certbot-auto --apache delete --cert-name uweheuer.goip.de
// this also edits /etc/apache2/sites-enabled/000-default-le-ssl.conf
  • after Fritzbox 7490 to Fritzbox 7590
./certbot-auto -d uweheuer.spdns.de --cert-name 36jjbpz29h1pyywz.myfritz.net
sudo /usr/local/bin/certbot-auto delete --cert-name bbx0axbhewglhzf4.myfritz.net
replace in /etc/apache2/sites-enabled/000-default-le-ssl.conf bbx0axbhewglhzf4 with 36jjbpz29h1pyywz
  • edit file /etc/cron.d/certbot and decomment old entry from obsolete installation and add
0 0,12 * * * python -c 'import random; import time; time.sleep(random.random() * 3600)' && /usr/local/bin/certbot-auto renew
Manual renew of SSL certificates[edit]
  • login as root@raspberrypi with <STANDARD>:
cd /usr/local/bin 
./certbot-auto renew // this might take very long if an update is needed, obviously requires reboot for JBoss to work properly
  • easiest is to reboot and than restart Wildfly (Wildfly is not startet automatically after reboot)

TCPDump[edit]

  • sudo apt-get install tcpdump

UweHeuer[edit]

  • create database mysql505 with PHPMyAdmin
  • export and import database
  • create /wildfly/wildfly-11.0.0.Final/standalone/data/uweheuer
  • copy abc.tmp and /wildfly/wildfly-11.0.0.Final/standalone/data
  • download mysql-connector-java-5.1.44-bin.jar from MySQL site
  • deploy it via the Wildfly admin console
  • create datasources via Web admin console with
MySQLDS (see File:RaspberryMySQL505Configuration.pdf)
jdbc:mysql://localhost/mysql505?autoReconnect=true
root root
...
UwesWikiDS
...

ProxyPass /uweheuer ajp://localhost:8009/uweheuer
ProxyPassReverse /uweheuer http://localhost/uweheuer
ProxyPass /uweheuer_qa ajp://localhost:8009/uweheuer_qa
ProxyPassReverse /uweheuer_qa http://localhost/uweheuer_qa
  • /etc/apache2/sites-available/000-default.conf permanent redirect to SSL
RedirectMatch ^/$ https://uweheuer.spdns.de/wordpress
Redirect /uweheuer https://uweheuer.spdns.de/uweheuer
Redirect /uweheuerqs https://uweheuer.spdns.de/uweheuerqs
Redirect /owncloud https://uweheuer.spdns.de/owncloud
  • create /myprogs and copy DisAndEnableUweHeuer.bat
  • Wildfly logger configuratoin according to here
  • after deployment uweheuer.war is probably extracted to (vfs stands for virtual file system)
/home/uwe/raspberry_root/wildfly/wildfly-11.0.0.Final/standalone/tmp/vfs/temp

Backup August 2025[edit]

  • C:\Uwes\owncloud\batches\Raspberry3BBookmarksToCTemp.bat Window cmd batch (not Powershell) to copy DB content for uweheuer to C:\temp

Backup[edit]

  • on laptop (xampp must be running)
    • create DB mysql506
    • run script
C:\Uwes\Batches\RaspberryBookmarksToLocalhost.bat
    • rename DB with date extension
  • on Raspberry map ubunturoot
mysqldump --single-transaction -h localhost -u root -p  mysql506 > /media/ubunturoot/backup/raspberry/uweheuer/mysql506_<YYYY-MM-DD>.txt
Enter password:
    • copy /wildfly/wildfly-19.1.0.Final/data/uweheuer/abc.tmp|Configuration.properties to /media/ubunturoot/backup/raspberry/uweheuer/
    • copy files to external discs

Wildfly 19.1[edit]

Installation[edit]

unzip wildfly-19.1.0.Final.zip // creates directory wildfly-19.1.0.Final
  • enable remote access to Wildfly by editing /wildfly/wildfly-19.1.0.Final/standalone/configuration/standalone.xml and replace (save old version to standalone.xml_20190609):
<interface name="management">
  <inet-address value="${jboss.bind.address.management:127.0.0.1}"/>
</interface>
<interface name="public">
  <inet-address value="${jboss.bind.address:0.0.0.0}"/>
</interface>
with
<interface name="management">
  <any-address/>
</interface>
<interface name="public">
  <any-address/>
</interface>
  • enable remote CLI access by adding native interface configuration to /wildfly/wildfly-19.1.0.Final/standalone/configuration/standalone.xml
// add to <socket-binding-group name="standard-sockets" ...
<socket-binding name="management-native" interface="management" port="${jboss.management.native.port:9999}"/>
// add to <management-interfaces>
<native-interface security-realm="ManagementRealm">
  <socket-binding native="management-native"/>
</native-interface>
  • because of experience with Wildfly 11 (see /var/log/syslog) copy /wildfly/wildfly-19.1.0.Final/bin/standalone.conf to standalone.conf_20200609 and edited to:
 -Xmx256m (from Xmx512m)
  • to make jsp work
cd /wildfly/wildfly-19.1.0.Final/standalone
chmod -R 777 tmp
  • add management user by
../bin/add-user.sh
Management User uweheuer <Lj>Halloo0@1<Lj> no groups
  • add Ajp Configuration -> Web- > Server -> default-server -> view -> Listener -> AJP Listener -> add -> 'ajp' 'ajp'
  • activate audit.log by changing <audit-log> section to enabled
<logger log-boot="true" log-read-only="false" enabled="true">
UweHeuer app preparation[edit]
Name: MySQLDS
JNDI Name: java:jboss/datasources/MySQLDS
Connection URL: jdbc:mysql://localhost/mysql506?autoReconnect=true
Driver Name: mysql-connector-java-5.1.44-bin.jar_com.mysql.jdbc.Driver_5_1
  • create uweheuer logger (set use parent handler to false)

Operation[edit]

cd /wildfly/wildfly-19.1.0.Final/standalone/log
  • check server status
cd /wildfly/wildfly-19.1.0.Final/bin
./jboss-cli.sh -c --commands="read-attribute server-state"

cd /wildfly/wildfly-19.1.0.Final/bin
./standalone.sh &
disown
./jboss-cli.sh --connect command=:shutdown

Wildfly 11 (obsolete)[edit]

  • create /wildfly directory and chmod 777
  • copy wildfly-11.0.0.Final.zip to /wildfly
  • unzip
  • enable remote access to Wildfly by editing /wildfly/wildfly-11.0.0.Final/standalone/configuration/standalone.xml and replace (save old version to standalone.xml_20171110):
<interface name="management">
  <inet-address value="${jboss.bind.address.management:127.0.0.1}"/>
</interface>
<interface name="public">
  <inet-address value="${jboss.bind.address:0.0.0.0}"/>
</interface>
with
<interface name="management">
  <any-address/>
</interface>
<interface name="public">
  <any-address/>
</interface>
  • enable remote CLI access by adding native interface configuration to /wildfly/wildfly-11.0.0.Final/standalone/configuration/standalone.xml (save old version to standalone.xml_20171112)
  • set Wildfly as a service by (there is a debian script in the doc directory and a description in the internet, but it didn't work, so the following approach from HomePC New) was used:
create /etc/init.d/uweswildflyuweswildfly
sudo chmod 755 /etc/init.d/uweswildfly
sudo update-rc.d uweswildfly defaults // log goes to /var/log/uwes.log
  • because of termination of java by operating system (see /var/log/syslog) for a test edited /wildfly/wildfly-11.0.0.Final/bin/standalone.conf:
 -Xmx256m (from Xmx512m)
  • to make jsp work
cd /wildfly/wildfly-11.0.0.Final/standalone
chmod -R 777 tmp
  • enable ajp communication to Apache2 by Web admin -> Configuration -> Subsystems -> Web/HTTP - Untertow -> Http -> View -> default server -> View -> AJP Listeners -> Add 'ajp' 'ajp'
  • deployments gets extracted to (vfs stands for virtual file system)
/home/uwe/raspberry_root/wildfly/wildfly-11.0.0.Final/standalone/tmp/vfs/temp

Manual Operation[edit]

  • cd /wildfly/wildfly-11.0.0.Final/bin
  • start server by reboot or by
./standalone.sh &
disown
  • stop server by
./jboss-cli.sh --connect command=:shutdown
  • restart server by
./jboss-cli.sh --connect command=:reload
  • get server status by
./jboss-cli.sh -c --commands="read-attribute server-state"

Wordpress[edit]

Installation[edit]

cd /var/wwww/html
wget https://wordpress.org/latest.zip
unzip latest.zip
sudo chown -R www-data:www-data wordpress

user = uwe.heuer@gmail.com
password = Halloo0@1

Increased maximum upload file size by editing PHP.INI.

Operation[edit]

Login[edit]

from Ubunut: 

ssh root@192.168.178.35

from Windows: 

WinSCP

Show Free Diskspace[edit]

df -h

Ports[edit]

netstat -tulnp

Analyze Network Access[edit]

From http://www.lug-erding.de/artikel/nts.html: 

telnet <IP|Domain> 80
GET / HTTP/1.1
<ENTER>
Host: <Domain>
<ENTER><ENTER>

If 

Trying <IP>

then name resolution works and if 

Connected to <IP|Domain>

then TCP is fine and errors are located in higher layers. If 

Connection refused

then probably no one listening at port or firewall otherwise see answer. 

ping -c <NumberOfPings> -s <Size>

If size is e.g. 4000 pakets have to fragmented which could give hints for the error. 

traceroute -n <IP> // Linux
tracert <IP> // Windows

DNS problems could be checked 

nslookup <Domain>

Detailled analysis via 

tcpdump

Reboot[edit]

sudo reboot

or via browser implemented by reboot.html and reb.php and adding to /etc/sudoers: 

www-data ALL=(root) NOPASSWD: /sbin/reboot

Shutdown[edit]

sudo shutdown -h 0

Update[edit]

sudo apt-get update // will update package list
sudo apt-get dist-upgrade

Error corrected according to here

Version[edit]

cat /etc/os-release
PRETTY_NAME="Raspbian GNU/Linux 8 (jessie)"
NAME="Raspbian GNU/Linux"
VERSION_ID="8"
VERSION="8 (jessie)"
ID=raspbian
ID_LIKE=debian
HOME_URL="http://www.raspbian.org/"
SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"
Retrieved from "http://uweheuer.spdns.de/mediawiki_new/index.php?title=RaspberryPi3B&oldid=11333"