Now that my FreeNAS install has been running for some time in ‘Production’ with no problems, I decided to do a little housekeeping to help offset potential downtime by creating a mirror for the USB boot drive incase it fails one day.
The option to create a mirrored boot drive is presented during the initial FreeNAS install, however I didn’t have another USB of the same make/model handy at the time. Fast forward to the present, having now found a spare USB that is identical to the one already installed (SanDisk Cruzer Fit USB 2.0 32GB) it was time to finish the job.
FreeNAS’ excellent documentation quickly goes over the process of retroactively creating the mirrored drive. Which seemed easy enough until I ran into the following error.
MiddlewareError: Failed to attach disk: cannot attach da1p2 to da0p2: device is too small
Cut a long story short after a couple hours of messing around with both USB drives, I discovered the new drive was ever so slightly smaller in capacity than the original even though both are 32GB. According to the documentation the new drive must either the same size or larger than the original, I didn’t realise it was just so picky on exact capacity.
dan@freenas /% gpart show => 34 62530557 da0 GPT (29G) 34 1024 1 bios-boot (512k) 1058 6 - free - (3.0k) 1064 62529520 2 freebsd-zfs (29G) 62530584 7 - free - (3.5k) => 34 61055997 da1 GPT (29G) 34 1024 1 bios-boot (512k) 1058 6 - free - (3.0k) 1064 61054960 2 freebsd-zfs (29G) 61056024 7 - free - (3.5k)
As you can see in the above snippet da0 has a total of 62530557 blocks compared to da1 which has a total of 61055997 (meaning da0 > da1).
After some more messing around and speaking to some folks on FreeNAS’ IRC I decided to do a reinstall of FreeNAS onto the smaller drive. I backed up my FreeNAS config (System -> General -> Save Config), shutdown the server, disconnected all my WD Red’s so they couldn’t interfere with the installation and began the fresh install.
Once complete, I restored the config (System -> General -> Upload config -> Reboot) and reconnected the WD Red’s to double checked the ZFS volume was still okay (precious precious data). With everything back up and running I installed the other USB stick and tried once again the mirroring process (System -> Boot -> Status -> freenas-boot -> Attach), which I’m happy to report completed successfully after a few minutes.
Hopefully this is one resiliency feature I won’t have to rely on anytime soon, but one can never be too careful and there is no real excuse with USB drives being so cheap nowadays.
FYI 32GB is overkill really for a FreeNAS boot drive, 16GB will suffice just fine.
Spacewalk (not the EVA kind) is an open source (GPLv2) Linux systems management solution and is the upstream project for Red Hat Satellite. The main feature I wished to experiment with was the ability to manage multiple systems packages (upgrades) concurrently. The project also has several other main features, including;
- Inventory your systems (hardware and software information)
- Install and update software on your systems
- Collect and distribute your custom software packages into manageable groups
- Provision (kickstart) your systems
- Manage and deploy configuration files to your systems
- Provision and start/stop/configure virtual guests
- Distribute content across multiple geographical sites in an efficient manner
Taken directly from the official Spacewalk docs:
- Open outbound firewall ports 80, 443
- Inbound open ports 80, 443, 5222 (covered below later on)
- Storage for database: 250 KiB per client system + 500 KiB per channel + 230 KiB per package in channel (i.e. 1.1GiB for channel with 5000 packages)
- Storage for packages (default /var/satellite): Red Hat recommend 6GB per channel for their channels, I used 20GB for storage, as 10GB wasn’t enough
- 2GB RAM minimum, 4GB recommended
- Fully up-to-date underlying operating system running a vanilla installation (no user customisation performed yet, fresh system install)
There are 3 main repos to setup.
rpm -Uvh http://yum.spacewalkproject.org/2.4/RHEL/7/x86_64/spacewalk-repo-2.4-3.el7.noarch.rpm
cat > /etc/yum.repos.d/jpackage-generic.repo << EOF [jpackage-generic] name=JPackage generic #baseurl=http://mirrors.dotsrc.org/pub/jpackage/5.0/generic/free/ mirrorlist=http://www.jpackage.org/mirrorlist.php?dist=generic&type=free&release=5.0 enabled=1 gpgcheck=1 gpgkey=http://www.jpackage.org/jpackage.asc EOF
Spacewalk requires Java Virtual Machine 1.6.0 or greater which is available in the EPEL repo.
rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
Time to get on with the install 🙂
Spacewalk uses database server to store its primary data. It supports either PostgreSQL (version 8.4 and higher) or Oracle RDBMS. Lets install PostgreSQL and let Spacewalk configure the database for us.
yum install spacewalk-setup-postgresql
Install the Spacewalk package with support for PostgreSQL.
yum install spacewalk-postgresql
Configure the firewall
Enable inbound firewall (firewalld) ports 80 (http) and 443 (https).
firewall-cmd --add-service=http firewall-cmd --add-service=https
Afterwards we should be able to visit: https://hostname.yourdomain.com to create the Spacewalk admin account and finish the installation.
FreeNAS is an amazing software stack and purpose built for hosting dedicated file storage shares, so it makes for an excellent platform to host a Time Machine compatible network share for use with OS X.
I wanted to build a server that would provide a reliable backup location with data redundancy for multiple Macs, with the ability to scale the storage space to meet future needs. Something which the current line of Apple TimeCapsules don’t offer, not to mention they are expensive for what they offer.
This setup will allow any Mac on the local network to backup to a central server using Ethernet/Wireless. I have gone the extra mile and included the ability of being able to remotely backup my MacBook Pro when away in London to my FreeNAS server at home using my OpenVPN server, but that’s for another post.
To clarify this was my first time using FreeNAS, I had no prior experience with the platform before writing this guide, so anyone should be able to recreate my setup with no prior knowledge of FreeNAS. My post is an updated version of an existing article I found, but is also a result of my own trial and errors. It takes time to figure out what works and what doesn’t.
For storage I picked up 4 x WD Red 3TB for NAS (Inc WD Express Warranty) for £91.99 each (£183.98 total). I picked the 3TB over the 4TB partly because of cost, but namely for reliability as numerous forums discuss high failure rates for the 4TB models.
I decided to utilise one of my G7 HP MicroServers as a dedicated FreeNAS server. The 2 WD Red drives were installed for storage, as well as a 32GB SanDisk Cruzer for the FreeNAS OS. I also maxed out the 16GB Kingston ECC RAM to help cope with the ZFS filesystems (the minimum recommended is 8GB).
You need to have a working install of FreeNAS before you can attempt this guide. I won’t detail over the OS installation as it’s fairly simple and has been documented numerous times over online, without forgetting to mention the amazing documentation that comes with FreeNAS Doc.
FreeNAS 9.3 is the current release at time of writing and is what this guide is based on, although future versions should also work fine.
Create ‘time-machine’ Group
The first step is to create a system group for the Time-Machine share in preparation for adding users.
Under the ‘Account’ menu item, expand the ‘Groups’ item, then select ‘Add Group’. Note that in my screenshots I already have a group called ‘Time-Machine’, your system won’t have until you complete this step.
- Leave ‘Group ID’ to whatever it is by default
- Set ‘Group Name’ to ‘time-machine’
Leave everything else as default and click OK. Our newly created ‘time-machine’ group should be visible under the ‘Groups’ section now.
Create and Configure Time-Machine ZFS Dataset
Now it’s time to create the ZFS dataset which will be used to store the Time Machine backups. You must have a ZFS volume already created for this step, if you haven’t got one then you should go read through the ZFS primer in the FreeNAS docs.
- Set ‘Dataset Name’ to ‘Time-Machine’
- Set ‘Quota for this dataset’ to ‘1000 GiB’
In the section option we are specifying a quota for the dataset, effectively settings the size of available disk space for our Time Machine backups. Change the value if 1000 GiB is not suitable for your setup.
Leave everything else as default and click ‘Add Dataset’. Our newly created ‘Time-Machine’ dataset should be visible under the ‘Volumes’ section now.
Now we need to configure the permissions for our ‘Time-Machine’ dataset, so that our ‘time-machine’ group has read/write access.
Select the dataset (Time-Machine) and then select ‘Change Permissions’.
- Set ‘Owner (group)’ to ‘time-machine’
- Set ‘Mode’ checkboxes to the same as mine in the screenshot
Click ‘By setting the group owner to the ‘time-machine’ group, we are granting any users of that group read/write/execute permissions.
Create Time-Machine Users
Now it’s time to create a separate user to represent each computer that will use the FreeNAS server for Time Machine backups.
Under the ‘Account’ menu item, expand the ‘Users’ item, then select ‘Add User’.
Set the config as follows, but change the relevant information related to your setup:
- Leave ‘User ID’ to whatever it is by default
- Set ‘Username’ to ‘dans-macbook-pro’
- Ensure ‘Create a new primary group’ is deselected
- Set ‘Primary Group’ to ‘time-machine’
- Set ‘Full Name’ to ‘Dan’s MacBook Pro’
- Set ‘Password’ to something strong (mix of; uppercase, lowercase, numbers, 16 chars long)
Leave everything else as default and click OK. Our newly created ‘dans-macbook-pro’ should be visible under the ‘Users’ section now.
Create Time-Machine AFP Share
The last step on the FreeNAS server is to create the AFP Share that will broadcast the storage on the local network.
Under the ‘Sharing’ tab select the ‘Apple (AFP)’ menu item, and then select ‘Add Apple (AFP) Share’.
Ensure the wizard is in ‘Advanced Mode’ and then set the config as follows:
- Set ‘Name’ to ‘Time Machine’
- Set ‘Path’ to your ZFS dataset path
- Set ‘Allow List’ to ‘@time-machine’
- Ensure the ‘Time Machine’ box is checked
- Ensure the ‘Default file permission’ is set to the same as the screenshot
- Ensure the ‘Default directory permission’ is set to the same as the screenshot
Add Time Machine Backup to OS X
Finally the last step is to configure Time Machine itself to backup to the newly created share.
In OS X, select ‘Time Machine’ from within ‘System Preferences’, and then click the ‘Select Disk’ button.
All being well your FreeNAS AFP share should be listed. If you select to use the disk for Time Machine you will be prompted to enter the username and password for the FreeNAS user we created previously. That’s the last step, Time Machine should begin backing up shortly after adding the disk. I recommend that the first backup be completed over Ethernet instead of wireless as the initial backup can take considerable time.
I have used this setup for a couple of years now backing up 4/5 Mac’s with no real issues. Any problems I have ran into have most revolved around sudden shutdowns of the FreeNAS server midway through Time Machine backing up due to power cuts/loss. My Storage is setup using ZFS in striped mirrored mode, meaning I get the best of both for speed and disk redundancy.
Please let me know if you found this guide useful, or spot any mistakes above.
This article will provide a quick guide to installing and hosting your own OpenVPN server on CentOS 6.
First order of business is to ensure you have the Extra Packages for Enterprise Linux (EPEL) repository installed. This a Fedora Project special interest group (SIG) that maintains additional packages for RedHat based Enterprise Linux distributions. It will enable the install of the OpenVPN package.
rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm
OpenVPN installation and configuration
Install the OpenVPN package from the newly added EPEL repository. OpenVPN 2.3.7 is the current version available at the time of writing.
yum install openvpn
Some guides will recommend copying the sample OpenVPN configuration, but I prefer to create one from scratch as it creates a cleaner config file that is easy to read and understand. You can if you wish still copy over the sample and edit as necessary to continue following the guide. Skip the command below if you wish to create one from scratch.
cp /usr/share/doc/openvpn-*/sample/sample-config-files/server.conf /etc/openvpn/server.conf
Create/edit the newly copied server config
Insert the following to the config. You can omit the comments indicated by ‘#’ if you wish.
# Enable TLS and assume server role during TLS handshake. tls-server # Use UDP as the main protocol proto udp # Default OpenVPN port is 1194 port 1194 # Configure TAP interface, this allows for full-frame Ethernet packets to be sent. Useful for AFP required for remote OS X TimeMachine backups dev tap # IP Address allocation to clients for specified network/netmask. # The server will take the '.1' address (192.168.100.1). server 192.168.100.0 255.255.255.0 # Absolute paths for server cert's and keys (created later on). ca /etc/openvpn/ca.crt cert /etc/openvpn/server.crt key /etc/openvpn/server.key dh /etc/openvpn/dh2048.pem tls-auth /etc/openvpn/ta.key 0 # This is the network/subnet of your physical LAN the OpenVPN server will reside. # Without this clients will be unable to ping other computers located on the same network as the server. push "route 192.168.0.0 255.255.255.0" topology subnet # DNS servers to be pushed to clients push "dhcp-option DNS 188.8.131.52" push "dhcp-option DNS 184.108.40.206" # Drop privileges after initialisation to help improve security. user nobody group nobody persist-key persist-tun # Used by the client to detect server timeout. # Ping server every 10 seconds, assume timeout after 60. keepalive 10 60 ping-timer-rem # Enable compression comp-lzo adaptive # Run the process as a daemon daemon # Set logging verbosity, specify absolute paths for log files. verb 4 log-append /var/log/openvpn.log status /var/log/openvpn.status
Certificate and Key generation
Now the OpenVPN configuration is complete, we need to generate some certificates and keys using a package Easy-RSA. Time to install more dependencies.
yum install easy-rsa
With the dependancy installed, it’s time to copy some required files into place.
mkdir -m 700 -p /etc/openvpn/easy-rsa/keys cp -rp /usr/share/easy-rsa/2.0/* /etc/openvpn/easy-rsa
Now we edit the ‘vars’ file which contains all the necessary values for the Easy-RSA scripts to use.
Change the key variables listed below contained in the ‘vars’ file to reflect your information.
You can omit the comments indicated by ‘#’ if you wish.
export KEY_SIZE=2048 # Can be increased to 4096 if desired export CA_EXPIRE=3650 # 10 years CA expiration export KEY_EXPIRE=1095 # 3 year Certificates expiration export KEY_COUNTRY="GB" export KEY_PROVINCE="MyCounty" export KEY_CITY="MyCity" export KEY_ORG="MyOrg" export KEY_EMAIL="firstname.lastname@example.org" export KEY_OU="MyOrgUnit" export KEY_NAME="MyServer" export KEY_CN="server.example.com" # FQDN for server
We’ll now load the variables into the session and make sure the keys/ folder is empty using the clean-all script.
cd /etc/openvpn/easy-rsa source ./vars ./clean-all
Time to build the CA private key and certificate with a password. Press enter when prompted and use a strong password.
Now we build the server certificate. When prompted to enter the ca.key password, enter the password you used during CA creation in the previous step.
We generate our Diffie-Hellman key exchange file for the server. This can take a long time to generate depending on your computer.
The last step is to generate the tls-auth file
openvpn --genkey --secret keys/ta.key
It’s time to generate some client certificates.
This step can be repeated as many times as necessary to generate a unique certificate for each client. Replace ‘client’ with a unique name for each client.
Now we copy all of the generated files into the OpenVPN conf directory.
cd /etc/openvpn/easy-rsa/keys cp ca.crt server.crt server.key dh2048.pem ta.key /etc/openvpn
Packet forwarding needs to be enabled on the server, so first we open the config.
Then edit ‘ip_forward’ to 1 if it’s not already set.
net.ipv4.ip_forward = 1
Create an iptables rule that will enable the server to forward packets to the rest of the network, received from VPN clients.
iptables -t nat -I POSTROUTING -s 192.168.100.0/24 -o eth0 -j MASQUERADE
Save the firewall rules, enable the service to start automatically on boot and then restart the system.
service iptables save chkconfig openvpn on reboot
The server configuration part of this guide is over, now lets move onto the client configuration.
First we need to create the client config. Similar to the server config it’s easier to create a new client config from scratch.
Create a new file on your client called client.conf
Insert the following client config below. Replace example.com with the hostname/IP address of your OpenVPN server.
client proto udp remote example.com port 1194 dev tap nobind ca ca.crt cert client.crt key client.key tls-auth ta.key 1 ns-cert-type server comp-lzo adaptive
Next is to copy over the required certificates and keys from the server. Use some form of transfer; USB drive, SCP, SFTP and move the ca.crt, client.crt, client.key and ta.key to the same directory as the client config.
Mac OS X OpenVPN Client
Now we are ready to load the config into a OpenVPN client and test our setup.
For OS X, Tunnelblink is the best OpenVPN client to use.
Opening the client.conf with Tunnelblink should kickstart the config install, which will load the config, keys and certificates into a Tunnelblink profile. Once complete you should be able to successfully connect to your OpenVPN server.
To test connectivity you should be able to ping the OpenVPN server from the client, as well as Google’s DNS server to confirm external connectivity.
ping 192.168.100.1 ping 220.127.116.11