GlusterFS Configuration

Assume node1 is: 192.168.33.10
Assume node2 is: 192.168.33.11

Sources:
https://www.digitalocean.com/community/tutorials/how-to-create-a-redundant-storage-pool-using-glusterfs-on-ubuntu-servers
http://www.jamescoyle.net/how-to/457-glusterfs-firewall-rules

On BOTH nodes

# set hosts file entry (or configure DNS)
vim /etc/hosts
192.168.33.10 gluster1
192.168.33.11 gluster2

# On Ubuntu: install requirements 
sudo add-apt-repository ppa:semiosis/ubuntu-glusterfs-3.5
sudo apt-get update
sudo apt-get install glusterfs-server
sudo apt-get install glusterfs-client

# On Centos: install requirements

wget -P /etc/yum.repos.d http://download.gluster.org/pub/gluster/glusterfs/LATEST/RHEL/glusterfs-epel.repo

yum install glusterfs-server

yum install glusterfs-client

# make storage location for gluster data
sudo mkdir /gluster-storage

# make a mountpoint
sudo mkdir /mnt/media/

ON GLUSTER 1

# connect node 1 and node 2
sudo gluster peer probe gluster2
sudo gluster peer status

# create a Gluster replica volume
sudo gluster volume create volume1 replica 2 transport tcp \

      gluster1:/gluster-storage \

      gluster2:/gluster-storage force

# list volumes
sudo gluster volume list

# start the gluster volume
sudo gluster volume start volume1

# mount the volume
sudo mount -t glusterfs gluster1:/volume1 /mnt/media/

# only allow given ips
sudo gluster volume set volume1 auth.allow gluster1,gluster2

sudo gluster volume info
sudo gluster volume profile volume1 start
sudo gluster volume profile volume1 info
sudo gluster volume status

# stop the volume
sudo gluster volume stop volume1

FSTAB Entries

** ON Gluster 1
gluster1:/volume1 /mnt/media/ glusterfs defaults,_netdev,backupvolfile-server=gluster2 0 0

** ON Gluster 2
gluster2:/volume1 /mnt/media/ glusterfs defaults,_netdev,backupvolfile-server=gluster1 0 0

systemd quickstart

Source:
https://fedoraproject.org/wiki/SysVinit_to_Systemd_Cheatsheet
https://wiki.ubuntu.com/SystemdForUpstartUsers
http://wiki.nginx.org/FedoraSystemdServiceFile

Start/stop/reload a service:
service foo start   # or
systemctl start foo

service foo stop   # or 
systemctl stop foo

service foo restart   # or 
systemctl restart foo

Reload a service using reload signal:
service foo reload

See if service is running:
service foo status   # or 
systemctl status foo

See tree listing of all services:
systemctl status

See job log: 
sudo journalctl -u foo -f

Enable a service (to start on boot):
systemctl enable foo

Disable a service:
systemctl disable foo

Service Definition Directory:
/lib/systemd/system/

Example Nginx Service: /lib/systemd/system/nginx.service 

[Unit]
Description=The nginx HTTP and reverse proxy server
After=syslog.target network.target remote-fs.target nss-lookup.target

[Service]
Type=forking
PIDFile=/run/nginx.pid
ExecStartPre=/usr/sbin/nginx -t
ExecStart=/usr/sbin/nginx
ExecReload=/bin/kill -s HUP $MAINPID
ExecStop=/bin/kill -s QUIT $MAINPID
PrivateTmp=true

[Install]
WantedBy=multi-user.target


Links:
https://scottlinux.com/2014/12/08/how-to-create-a-systemd-service-in-linux-centos-7/

Simple ClamAV Usage

Source: Nice Resource
http://askubuntu.com/questions/250290/how-do-i-scan-for-viruses-with-clamav

Install:
sudo apt-get install clamav

Refresh virus definition database:
sudo freshclam

Scan all files on computer showing each
clamscan -r /

Only display infected files and ring bell
clamscan -r --bell -i /

Scan all files and move them to infected dir
clamscan -r --move=/home/USER/VIRUS /home/USER

Scan all files and remove bad ones
clamscan -r --remove /home/USER