Tag: DNS

  • LetsEncrypt it!

    Hello, Quite a quick turnaround for blog posts and me. This one is going to be helpful for those of us that use Wildcard Certificates in our environment and found out that our SSL provider changed their policies based on industry standards, but now their certificates cost 200x more than they used to so we are moving to an opensource and free solution.

    For those of you that don’t know what the previous paragraph means, Google, and other major web site providers implemented that all communications on the Internet be secured. To do this, we use SSL or Secure Socket Layer certificates. These certificates verify and validate that the site you are on is the real one and any information that you provide on it will be encrypted and secure. SSL Certificate do this encrypting and signing to make sure everything is good. In the past, we used to have to spend $100’s, if not $1000’s (Like it did) to have this capability. LetsEncrypt came about to make this free and accessible to everyone. The downside is that the certificates are only valid for 90 days instead of a year, but you get what you pay for.

    I am moving to this model because my vendor of SSL, Digicert changed their model and now I can’t renew certificates without spending another $600 on top of the $5k I’ve already spent. So I am moving to LetsEncrypt.

    LetsEncrypt is a SSL company that uses a software package called certbot that can automatically create and install certificates that are trusted to systems.

    My DNS host provider, however, is not one of their partners. However, they do allow me to edit records on the fly, which is important since that is how LetsEncrypt verifies that you own the domain and won’t generate a certificate if you don’t. This means that I can’t automate the deployment or the generation, and I have to run the following command to update my certificates every 90 days. Some of my systems can be automated, which those, like this one that runs my web server, can. However, I do have some systems like my Virtual Center server or my Email server that use Wildcard or a single certificate to cover multiple servers. This blog will discuss how to do this, mainly so that in 90 days I can remember how to do this.

    So, on to how to do this.

    First, install certbot on a machine. Since I’m a Linux person, and I used Ubuntu, I installed this on my local machine:

    sudo apt update
    sudo apt install letsencrypt

    This installs the base LetsEncrypt software with no plugins. Since my DNS provider does not have a plugin, I have to do this manually.

    I also had to add the wildcard, or “*” to my domain to prove I owned the domain, so I logged in to my DNS provider, and created an “A” record that pointed to my webserver with the *.lucaswilliams.net name. This will allow me to use this certificate on any of my server inside my lucaswilliams.net domain. Very useful for virtual server for VMware, email, and other servers that need HTTPS and SSL Certificates.

    Once I created the wildcard domain entry in my DNS record. I then went to the terminal on my Linux machine and typed the following:

    sudo certbot certonly --manual \
    --preferred-challenges=dns \
    --email user@domain.com \
    --server https://acme-v02.api.letsencrypt.org/directory \
    --agree-tos \
    -d *.domain.com

    for the --server https://acme-v02.api.letsencrypt.org/directory line, you have to use this server to create the certificate as this is the only one that LetsEncrypt uses to for this requirement.

    After hitting enter to start the process, I was presented a prompt asking if I wanted to share my information and details about the certificate, which I replied “N” but if you want you can.

    The next prompt is the important one. It looks like the following:

    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    Please deploy a DNS TXT record under the name:
    
    _acme-challenge.domain.com.
    
    with the following value:
    
    q12yr1dyFyrh143HHRTe42HH_hf#1d7&ewftgs8H
    
    Before continuing, verify the TXT record has been deployed. Depending on the DNS
    provider, this may take some time, from a few seconds to multiple minutes. You can
    check if it has finished deploying with aid of online tools, such as the Google
    Admin Toolbox: https://toolbox.googleapps.com/apps/dig/#TXT/_acme-challenge.domain.com.
    Look for one or more bolded line(s) below the line ';ANSWER'. It should show the
    value(s) you've just added.
    
    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    Press Enter to Continue

    I then logged into my DNS provider and created this TXT record and then hit enter in the terminal to complete the key generation. LetsEncrypt verified the record and created my certificates in /etc/letsencrypt/live/domain.com. You will need ‘root’ access for the live directory, so I ran sudo -i to change to root user and access the certificates.

    I then copied the privekey.pem and fullchain.pem files to my servers and renamed them to what the system understands as the private key file and the certificate file.

    The biggest takeaway from this is that LetsEncrypt will let us create certificates for our systems for free, however, they only are valid for 90 days which means that we have to do this every 3 months. Some systems can be fully automated if their names don’t change or the certificate is used only for validation and verification of the site and name, but more complex certificates, like email verification and signature signing, this is the way to go for that.

    If any of you know of a better way of doing this, please let me know and I’ll share it and give you credit for the improvment!

  • MAAS 2.0 and DNS

    Hello everyone! Been a while since I wrote a blog entry. I updated my network topology last night to accommodate for guest access and to separate my personal network from my work network to keep my video game consoles and my cell phones off of my external facing network and firewall them up better for more security. I decided during this time as well to revisit my DNS and Virtual Host machines.

    I was running ESXi 6 on one of my hosts that ran Ubuntu VM’s for this site, and my email server, and a couple other servers that I use to do my job. It became a hassle to keep it up and running on older hardware so I upgraded it to KVM and Ubuntu 16.04 and I decided that I would also upgrade my VM’s from 14.04 LTS to 16.04 LTS since I had the downtime.

    Anyways, I decided that I was going to use MAAS, or Canonical’s Metal-As-A-Service to provision my KVM’s and also get rid of my aging DHCP/DNS server that was running 12.04 and just move everything to MAAS. Sounds easy enough? Not so much.

    Building the KVM host was easy. I installed Ubuntu 16.04, selected OpenSSH server and Virtual Machine Host from the TaskSel and then after it was installed, ran sudo apt update && sudo apt upgrade, rebooted, and then ran sudo apt install ovmf qemu and modified my /etc/libvirt/qemu.conf to point to where ovmf was (basically just removed the comments from the file for those settings) and than ran systemctl restart libvirt-bin and was ready to go. I also modified my NIC interfaces to bridges.

    Now I was ready to build my MAAS server. I build a KVM with 2GB of RAM and 2 processors and 60GB of storage and added 2 NIC’s, one for each of my networks, one for my servers and external network, and one for my internal guest network. I installed a clean 16.04 LTS server, added OpenSSH and configured the interfaces for static addresses and ran update/upgrade and now was ready to install MAAS. I ran sudo apt install maas and was off and running. After it was complete, I ran sudo maas createadmin to create the admin account. I then logged in to maas by opening Firefox and browsing to my maas servers IP address and logging in. I click on my account in the upper right corner and went to Account, and copied my API key to a file called maas.key in my home directory on MAAS so that when I need to use the CLI, I can just cat maas.key instead of having to type the whole damn thing in. I then copied all my SSH keys to my account so that I can access my new nodes with my SSH key, and I then went to the Images tab to make sure it was downloading the 16.04 image, and did some minor settings to make sure it seen all my networks and put in my DNS forwarders.

    Next, it was time to setup DHCP. I clicked on the Network tab and clicked on the subnet I wanted to have DHCP. I set a dynamic reservation for my internal network starting at .50 and going to .200. I then clicked my other subnet and did the same thing there. I then went back to the Network tab and clicked the VLAN for each of my fabrics. Under the Take Action button, I configured DHCP for this network and was ready to go.

    I built my webserver as a KVM, and told it to PXE boot and attach it to the server network bridge on my KVM host. I powered it up and boom! MAAS found it, and enlisted the node. I changed its name, but realized it was not using my DNS name, but instead the MAAS default of “maas.” According to Canonical’s documentation on MAAS, you can change this from the WebUI. That would be helpful to tell a user how, but I’m not going to go there. In 1.9, it was as easy as clicking the domain name on the Nodes tab, but in 2.0, not so much. I ended up changing it from the MAAS CLI by ssh’ing into my MAAS server and running the following command to login:

    maas login maas http://maas/MAAS `cat ~/maas.key`

    I then ran maas maas domain update name=lucaswilliams.net and verified that it was updated with maas maas domains read and in the MAAS WebUI, it updated it as well.

    I then clicked on my new node, and commissioned it. After 10 minutes, it was commissioned and ready for deployment. I deployed, which I have to say, is a huge improvement over 1.9. In the node tab, under Interfaces, I could statically set my IP address, which I did, and then I clicked deploy, and from the pull down said 16.04 and it was off. About 20 minutes go by, and it’s done. Now, I ssh into my new server and I can login with my SSH keys from my various workstations and it works. I then go through the process of installing LAMP on the server and getting WordPress configured and recovering my site from my backup. Then I notice that I don’t have my CNAME records to access my server via www or wordpress. I go into research mode. How do I add CNAME’s to MAAS 2.0 DNS? Great news, according to Canonical’s maas.io site, you can do this, but once again, they don’t tell you how. After spending hours doing Google-Fu and on freenode asking around, to no avail, I decided “Whats the worse that can happen?” I start poking through the MAAS source on the dnsresource flags and relize that there is an option in the MAAS CLI for dnsresource-records. I look into that and low and behold, it tells you there I can create A, AAA, CNAME, MX, SRV, NS and TXT records. So, through about 2 hours of trial and error, I finally figured it out:

    maas maas dnsresource-records create fqdn=www.lucaswilliams.net rrtype=cname rrdata=webserver

    It shown the record in the DNS tab in MAAS as well. I was able to ping the new CNAME and it responded properly. You are able to see this page as a result of it working as well.

    I did the exact same above steps for my mail server as well, however, I had to create a MX record for it since it was failing its install step doing an MX record lookup. Great, how do I do that? Luckily, after only an hour of trial and error, I figured it out:

    maas maas dnsresource-records create fqdn=lucaswilliams.net rrtype=mx rrdata='10 mail.lucaswilliams.net'

    It updated in the DNS tab in MAAS and I could see all of these with the MAAS CLI. I was also able to add static servers that were not commissioned by MAAS into DNS via the CLI with the following command:

    maas maas dnsresources create fqdn=hostname.lucaswilliams.net ip_addresses=ip.add.re.ss

    Anything that is DHCP assigned will populate DNS automagically.

    And there you have it, a way to add MX and CNAME records so that you don’t have to do the research, or if you Google search it, hopefully you fall here.

    Let me know in the comments if this helps you or not, and let me know what else you want to know about.