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Introducing Incredible PBX 11-12 with Incredible GUI for the Ubuntu 14 Platform
On May 15, we turned the page on Asterisk® GUIs by introducing a new GUI that hopefully provides the best of both worlds. It preserves the GPL components of the FreePBX® product that many of us have nurtured for almost a decade while removing the commercial pieces that have introduced some friction into the equation for users and companies that simply wished to deploy or redistribute a graphical user interface for Asterisk in accordance with the free GPL licenses under which the product and its components were licensed. Last week we did much the same thing with the essential cloud component which serves as the lynchpin for GPL module administration within the GUI itself. Hopefully, these two tweaks will encourage Sangoma, the new owner of the FreePBX project, to do the right thing and get the non-commercial pieces of the project back on the right track moving forward. What we did not want to do was tarnish the incredibly hard work that dozens of developers in the open source community have poured into this project over the past decade. We continue to be amazed at what they’ve been able to achieve, and we salute their accomplishments. The Asterisk 12 and 13 revolution never would have been achieved without the contributions of the FreePBX development team. We think the new Incredible PBX GUI stands as a testament to what can be accomplished while preserving the true spirit of open source development and the terms of the GPL licenses under which this product and its numerous modules were licensed.
Two weeks ago, we introduced the all-new Incredible PBX with Incredible GUI for CentOS, Scientific Linux, and Oracle Linux. Last week we added a Cloud-based GPL repository and all the tools necessary to maintain it. Today we’re pleased to release the production-ready version for the Ubuntu 14 platform with all the bells and whistles including Incredible Fax featuring HylaFax and AvantFax. Today’s release mimics the functionality of the previous build for the CentOS platform with literally dozens of turnkey applications that show off the very best features of Asterisk®. In addition to Incredible PBX, you also get our new GPL repository to maintain release 12 of the GUI. No strings, no gotchas, and no murky licenses. Pure GPL!
Building an Ubuntu 14.04 Platform for Incredible PBX
As a result of the trademark and copyright morass, we’ve steered away from the bundled operating system in favor of a methodology that relies upon you to put in place the operating system platform on which to run PBX in a Flash or Incredible PBX. The good news is it’s easy! With many cloud-based providers1, you can simply click a button to choose your favorite OS flavor and within minutes, you’re ready to go. With many virtual machine platforms such as VirtualBox, it’s equally simple to find a pre-built Ubuntu 14.04 image or roll your own.
If you’re new to VoIP or to Nerd Vittles, here’s our best piece of advice. Don’t take our word for anything! Try it for yourself in the Cloud! You can build an Ubuntu 14.04 image on Digital Ocean in under one minute and install today’s Incredible PBX for Ubuntu 14.04 in about 15 minutes. Then try it out for two full months. It won’t cost you a dime. Use our referral link to sign up for an account. Enter a valid credit card to verify you’re who you say you are. Create an Ubuntu 14.04 (not 14.10!) 512MB droplet of the cheapest flavor ($5/mo.). Go to the Billing section of the site, and enter the following promo code: UBUNTUDROPLET. That’s all there is to it. A $10 credit will be added to your account, and you can play to your heart’s content. Delete droplets, add droplets, and enjoy the free ride!
For today, we’ll walk you through building your own stand-alone server using the Ubuntu 14.04 mini.iso. If you’re using Digital Ocean in the Cloud, skip down to Installing Incredible PBX 11-12 (HINT: 11 tells you the Asterisk release and 12 tells you the GUI release). If you’re using your own hardware, to get started, download the 64-bit Ubuntu 14.04 "Trusty Tahr" Minimal ISO from here. Then burn it to a CD/DVD or thumb drive and boot your dedicated server from the image. Remember, you’ll be reformatting the drive in your server so pick a machine you don’t need for other purposes.
For those that would prefer to build your Ubuntu 14.04 Wonder Machine using VirtualBox on any Windows, Mac, or existing Linux Desktop, here are the simple steps. Create a new virtual machine specifying the 64-bit version of Ubuntu. Allocate 1024MB of RAM (512MB also works fine with a swap file) and at least 20GB of disk space using the default hard drive setup in all three steps. In Settings, click System and check Enable I/O APIC and uncheck Hardware Clock in UTC Time. Click Audio and Specify then Enable your sound card. Click Network and Enable Network Adapter for Adapter 1 and choose Bridged Adapter. Finally, in Storage, add the Ubuntu 14.04 mini.iso to your VirtualBox Storage Tree as shown below. Then click OK and start up your new virtual machine. Simple!
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Here are the steps to get Ubuntu 14.04 humming on your new server or virtual machine once you’ve booted up. If you can bake cookies from a recipe, you can do this:
UBUNTU mini.iso install:
Choose language
Choose timezone
Detect keyboard
Hostname: incrediblepbx < continue >
Choose mirror for downloads
Confirm archive mirror
Leave proxy blank unless you need it < continue >
** couple minutes of whirring as initial components are loaded **
New user name: incredible < continue >
Account username: incredible < continue >
Account password: makeitsecure
Encrypt home directory < no >
Confirm time zone < yes >
Partition disks: Guided - use entire disk and set up LVM
Confirm disk to partition
Write changes to disks and configure LVM
Whole volume? < continue>
Write changes to disks < yes> < -- last chance to preserve your disk drive!
** about 15 minutes of whirring during base system install ** < no touchy anything>
** another 5 minutes of whirring during base software install ** < no touchy anything>
Upgrades? Install security updates automatically
** another 5 minutes of whirring during more software installs ** < no touchy anything>
Software selection: *Basic Ubuntu server (only!)
** another couple minutes of whirring during software installs ** < no touchy anything>
Grub boot loader: < yes>
UTC for system clock: < no>
Installation complete: < continue> after removing installation media
** on VirtualBox, PowerOff after reboot and remove [-] mini.iso from Storage Tree & restart VM
login as user: incredible
** enter user incredible's password **
sudo passwd
** enter incredible password again and then create secure root user password **
su root
** enter root password **
apt-get update
apt-get install ssh -y
sed -i 's|without-password|yes|' /etc/ssh/sshd_config
sed -i 's|yes"|without-password"|' /etc/ssh/sshd_config
sed -i 's|"quiet"|"quiet text"|' /etc/default/grub
update-grub
ifconfig
** write down the IP address of your server from ifconfig results
reboot
** login via SSH to continue **
Installing Incredible PBX 11-12 on Your Ubuntu 14.04 Server
Adding Incredible PBX 11-12 to a running Ubuntu 14.04 server is a walk in the park. To restate the obvious, your server needs a reliable Internet connection to proceed. Using SSH (or Putty on a Windows machine), log into your new server as root at the IP address you deciphered in the ifconfig step at the end of the Ubuntu install procedure above. First, make sure to run the update step for Ubuntu below before you begin the install. This is especially important if you’re using a cloud-based Ubuntu 14 server.
WARNING: As of early June, 2016, Ubuntu has introduced a bug in their latest MySQL upgrade. Do NOT run apt-get upgrade for the time being, or your Incredible PBX install will fail.
apt-get update && touch /root/COPYING
WARNING: If you’re using a 512MB droplet at Digital Ocean, be advised that the DO Ubuntu setup does NOT include a swap file. This may cause serious problems when you run out of RAM. Uncomment ./create-swapfile-DO line below to create a 1GB swap file which will be activated whenever you exceed 90% RAM usage on Digital Ocean.
Now let’s begin the Incredible PBX 11-12 install. Log back in as root and issue the following commands:
cd /root wget http://incrediblepbx.com/incrediblepbx11-12.2-ubuntu14.tar.gz tar zxvf incrediblepbx* #./create-swapfile-DO ./Incredible*
Once you have agreed to the license agreement and terms of use, press Enter and go have a 30-minute cup of coffee. The Incredible PBX installer runs unattended so find something to do for a bit unless you just like watching code compile. When you see "Have a nice day", your installation is complete. Write down your admin password for the GUI as well as your three "knock" ports for PortKnocker. If you forget your admin password or wish to change it, just run: /root/admin-pw-change. Retrieve your PortKnocker setup like this: cat /root/knock.FAQ.
Log out and back in as root and you should be greeted with a status display that looks something like this after the Automatic Update Utility runs:
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Perform the following steps:
Make your root password very secure: passwd
Set your correct time zone: ./timezone-setup
Restart Asterisk: amportal restart
Create admin password for web apps: htpasswd -b /etc/pbx/wwwpasswd admin newpassword
Make a copy of your other passwords: cat passwords.FAQ
Make a copy of your Knock codes: cat knock.FAQ
Decipher IP address and other info about your server: status
Incredible PBX includes an automatic update utility which downloads important updates whenever you log into your server as root. We recommend you log in once a week to keep your server current. Now would be a good time to log out and back into your server at the Linux command line to bring your server up to current specs.
You can access the Incredible PBX GUI using your favorite web browser to configure your server. Just enter the IP address shown in the status display.
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When the Kennonsoft menu (shown above) appears, click on the User tab to open the Admin menu. Then click on Incredible GUI Administration to access the Incredible PBX GUI. The default username is admin with the randomized password you wrote down above. If desired, you can change them after logging into the GUI by clicking Admin -> Administrators -> admin. Enter a new password and click Submit Changes then Apply Config. Now edit extension 701 so you can figure out (or change) the randomized passwords that were set up for default 701 extension and voicemail: Applications -> Extensions -> 701.
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Setting Up a Soft Phone to Use with Incredible PBX
Now you’re ready to set up a telephone so that you can play with Incredible PBX. We recommend YateClient which is free. Download it from here. Run YateClient once you’ve installed it and enter the credentials for the 701 extension on Incredible PBX. You’ll need the IP address of your server plus your extension 701 password. Choose Settings -> Accounts and click the New button. Fill in the blanks using the IP address of your server, 701 for your account name, and whatever password you created for the extension. Click OK.
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Once you are registered to extension 701, close the Account window. Then click on YATE’s Telephony Tab and place some test calls to the numerous apps that are preconfigured on Incredible PBX. Dial a few of these to get started:
123 - Reminders
222 - ODBC Demo (use acct: 12345)
947 - Weather by ZIP Code
951 - Yahoo News
*61 - Time of Day
*68 - Wakeup Call
TODAY - Today in History
The next step is establishing an interface on your PBX to connect to the telephones in the rest of the world. If you live in the U.S., the easiest way (at least for now) is to use an existing (free) Google Voice account. Google has threatened to shut this down but as this is written, it still works with previously set up Google Voice accounts. The more desirable long-term solution is to choose several SIP providers and set up redundant trunks for your incoming and outbound calls. The PIAF Forum includes dozens of recommendations to get you started.
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Configuring Google Voice
If you want to use Google Voice, you’ll need a dedicated Google Voice account to support Incredible PBX. If you want to use the inbound fax capabilities of Incredible Fax 11, then you’ll need an additional Google Voice line that can be routed to the FAX custom destination using the GUI. The more obscure the username (with some embedded numbers), the better off you will be. This will keep folks from bombarding you with unsolicited Gtalk chat messages, and who knows what nefarious scheme will be discovered using Google messaging six months from now. So keep this account a secret!
We’ve tested this extensively using an existing Google Voice account, and inbound calling is just not reliable. The reason seems to be that Google always chooses Gmail chat as the inbound call destination if there are multiple registrations from the same IP address. So, be reasonable. Do it our way! Use a previously configured and dedicated Gmail and Google Voice account, and use it exclusively with Incredible PBX 11.
IMPORTANT: Be sure to enable the Google Chat option as one of your phone destinations in Settings, Voice Setting, Phones. That’s the destination we need for The Incredible PBX to work its magic! Otherwise, all inbound and outbound calls will fail. If you don’t see this option, you’re probably out of luck. Google has disabled the option in newly created accounts as well as some old ones that had Google Chat disabled. Now go back to the Google Voice Settings.
While you’re still in Google Voice Settings, click on the Calls tab. Make sure your settings match these:
- Call Screening – OFF
- Call Presentation – OFF
- Caller ID (In) – Display Caller’s Number
- Caller ID (Out) – Don’t Change Anything
- Do Not Disturb – OFF
- Call Options (Enable Recording) – OFF
- Global Spam Filtering – ON
Click Save Changes once you adjust your settings. Under the Voicemail tab, plug in your email address so you get notified of new voicemails. Down the road, receipt of a Google Voice voicemail will be a big hint that something has come unglued on your PBX.
One final word of caution is in order regardless of your choice of providers: Do NOT use special characters in any provider passwords, or nothing will work!
Now you’re ready to set up your Google Voice trunk in the GUI. After logging in with your browser, click the Connectivity tab and choose Google Voice/Motif. To Add a new Google Voice account, just fill out the form. Do NOT check the third box or incoming calls will never ring!
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IMPORTANT LAST STEP: Google Voice will not work unless you restart Asterisk from the Linux command line at this juncture. Using SSH, log into your server as root and issue the following command: amportal restart.
If you have trouble getting Google Voice to work (especially if you have previously used your Google Voice account from a different IP address), try this Google Voice Reset Procedure. It usually fixes connectivity problems. If it still doesn’t work, enable Less Secure Apps using this Google tool.
And here’s another way to access Google Voice securely using an inexpensive commercial SIP gateway:
Troubleshooting Audio and DTMF Problems
You can avoid one-way audio on calls and touchtones that don’t work by entering these simple settings in the GUI: Settings -> Asterisk SIP Settings. Just plug in your public IP address and your private IP subnet. Then set ULAW as the only Audio Codec.
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Adding Speech Recognition to Incredible PBX
To support many of our applications, Incredible PBX has included Google’s speech recognition service for years. These applications include Weather Reports by City (949), AsteriDex Voice Dialing by Name (411), and Wolfram Alpha for Asterisk (4747), all of which use Lefteris Zafiris’ terrific speech-recog AGI script. Unfortunately (for some), Google now has tightened up the terms of use for their free speech recognition service. Now you can only use it for "personal and development use." If you meet those criteria, keep reading.
First, log into your server as root and issue the following commands:
# for Ubuntu and Debian platforms apt-get clean apt-get install libjson-perl flac -y # for RedHat and CentOS platforms yum -y install perl-JSON # for all Linux platforms cd /var/lib/asterisk/agi-bin mv speech-recog.agi speech-recog.last.agi wget --no-check-certificate https://raw.githubusercontent.com/zaf/asterisk-speech-recog/master/speech-recog.agi chown asterisk:asterisk speech* chmod 775 speech* nano -w speech-recog.agi
Here’s how to activate speech recognition on Incredible PBX. Don’t skip any steps!
Now you’re ready to try out the speech recognition apps. Dial 949 and say the name of a city and state/province/country to get a current weather forecast from Yahoo. Dial 411 and say "American Airlines" to be connected to American.
To use Wolfram Alpha by phone, you first must install it. Obtain your free Wolfram Alpha APP-ID here. Then run the one-click installer: /root/wolfram/wolframalpha-oneclick.sh. Insert your APP-ID when prompted. Now dial 4747 to access Wolfram Alpha by phone and enter your query, e.g. "What planes are overhead." Read the Nerd Vittles tutorial for additional examples and tips.
A Few Words about the Incredible PBX Security Model for Ubuntu
Incredible PBX for Ubuntu 14 is a very secure, turnkey PBX implementation. As configured, your server is protected by both Fail2Ban and a hardened configuration of the IPtables Linux firewall. Nobody can access your PBX without your credentials AND
an IP address that is either on your private network or that matches the IP address of your server or the PC from which you installed Incredible PBX. Incredible PBX is preconfigured to let you connect to many of the leading SIP hosting providers without additional firewall tweaking.
You can whitelist additional IP addresses for remote access in several ways. First, you can use the command-line utilities: /root/add-ip and /root/add-fqdn. You can also remove whitelisted IP addresses by running /root/del-acct. Second, you can dial into extension 864 (or use a DID pointed to extension 864 aka TM4) and enter an IP address to whitelist. Before Travelin’ Man 4 will work, you’ll need to add credentials for each caller using the tools in /root/tm4. You must add at least one account before dial-in whitelisting will be enabled. Third, you can temporarily whitelist an IP address by successfully executing the PortKnocker 3-knock code established for your server. You’ll find the details and the codes in /root/knock.FAQ. Be advised that IP addresses whitelisted with PortKnocker (only!) go away whenever your server is rebooted or the IPtables firewall is restarted. For further information on the PortKnocker technology and available clients for iOS and Android devices, review the Nerd Vittles tutorial.
HINT: The reason that storing your PortKnocker codes in a safe place is essential is because it may be your only available way to gain access to your server if your IP address changes. You obviously can’t use the command-line tools to whitelist a new IP address if you cannot gain access to your server at the new IP address.
We always recommend you also add an extra layer of protection by running your server behind a hardware-based firewall with no Internet port exposure, but that’s your call. If you use a hardware-based firewall, be sure to map the three PortKnocker ports to the internal IP address of your server!
The NeoRouter VPN client also is included for rock-solid, secure connectivity for remote users. Read our previous tutorial for setup instructions.
As one would expect, the IPtables firewall is a complex piece of software. If you need assistance configuring it, visit the PIAF Forum for some friendly assistance.
Adding Incredible Fax 11 to Your Server
Once you’ve completed the Incredible PBX install, log out and log back in to load the latest automatic updates. Then reboot. Now you’re ready to continue your adventure by installing Incredible Fax 11 for Ubuntu. Special thanks to Josh North for all his hard work on this! The latest download includes the Incredible Fax 11 installer. So just run the script:
cd /root ./incrediblefax11_ubuntu14.sh
Accept all of the defaults during the installation process. IMPORTANT: Once you complete the install, reboot your server. After rebooting, log into the GUI and choose Module Admin and enable the AvantFax module. When you log out of the GUI, there now will be an option for AvantFax on the GUI’s main login screen. Choose it and enter admin:password to login and change your default password. You also can set your AvantFax admin password by logging into the Linux CLI and… /root/avantfax-pw-change.
Incredible Backup and Restore
We’re pleased to introduce our latest backup and restore utilities for Incredible PBX. Running /root/incrediblebackup will create a backup image of your server in /tmp. This backup image then can be copied to any other medium desired for storage. To restore it to another Incredible PBX 11 server, simply copy the image to a server running Asterisk 11 and the Incredible PBX 11-12 GUI. Then run /root/incrediblerestore. Doesn’t get much simpler than that.
Incredible PBX Automatic Update Utility
Every time you log into your server as root, Incredible PBX will ping the IncrediblePBX.com web site to determine whether one or more updates are available to bring your server up to current specs. We recommend you log in at least once a week just in case some new security vulnerability should come along. Also be sure to check the PBX in a Flash RSS Feed inside the GUI for the latest security alerts.
Mastering the Incredible PBX Applications
Your next stop should be a quick read of the Application User’s Guide for Incredible PBX. Even though the target audience was Raspberry Pi users, the feature set is identical, and this guide will tell you everything you need to know about the dozens of applications for Asterisk that have been installed on your new server.
We also want to encourage you to sign up for an account on the PIAF Forum and join the discussion. In addition to providing first-class, free support, we think you’ll enjoy the camaraderie. Come join us!
Originally published: Monday, June 1, 2015
Support Issues. With any application as sophisticated as this one, you’re bound to have questions. Blog comments are a terrible place to handle support issues although we welcome general comments about our articles and software. If you have particular support issues, we encourage you to get actively involved in the PBX in a Flash Forums. It’s the best Asterisk tech support site in the business, and it’s all free! Please have a look and post your support questions there. Unlike some forums, ours is extremely friendly and is supported by literally hundreds of Asterisk gurus and thousands of users just like you. You won’t have to wait long for an answer to your question.
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Need help with Asterisk? Visit the PBX in a Flash Forum.
Special Thanks to Our Generous Sponsors
FULL DISCLOSURE: ClearlyIP, Skyetel, Vitelity, DigitalOcean, Vultr, VoIP.ms, 3CX, Sangoma, TelecomsXchange and VitalPBX have provided financial support to Nerd Vittles and our open source projects through advertising, referral revenue, and/or merchandise. As an Amazon Associate and Best Buy Affiliate, we also earn from qualifying purchases. We’ve chosen these providers not the other way around. Our decisions are based upon their corporate reputation and the quality of their offerings and pricing. Our recommendations regarding technology are reached without regard to financial compensation except in situations in which comparable products at comparable pricing are available from multiple sources. In this limited case, we support our sponsors because our sponsors support us.
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The lynchpin of Incredible PBX 2020 and beyond is ClearlyIP components which bring management of FreePBX modules and SIP phone integration to a level never before available with any other Asterisk distribution. And now you can configure and reconfigure your new Incredible PBX phones from the convenience of the Incredible PBX GUI.
VitalPBX is perhaps the fastest-growing PBX offering based upon Asterisk with an installed presence in more than 100 countries worldwide. VitalPBX has generously provided a customized White Label version of Incredible PBX tailored for use with all Incredible PBX and VitalPBX custom applications. Follow this link for a free test drive!
Special Thanks to Vitelity. Vitelity is now Voyant Communications and has halted new registrations for the time being. Our special thanks to Vitelity for their unwavering financial support over many years and to the many Nerd Vittles readers who continue to enjoy the benefits of their service offerings. We will keep everyone posted on further developments.
Some Recent Nerd Vittles Articles of Interest…
- With some providers including ones linked in this article, Nerd Vittles receives referral fees which assist in keeping the Nerd Vittles lights burning brightly. [↩]
Top 3 Asterisk Security Tips for 2014: WhiteLists, WhiteLists, and WhiteLists
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We’ve devoted a lot of energy to Asterisk security over the years with our Primer on Avoiding the $100,000 Phone Bill and our 20 Failsafe Tips and our SIP Navigation Guide plus numerous tutorials on deployment of Virtual Private Networks to secure your servers and phones including NeoRouter, PPTP, and Easy OpenVPN among others. But, when it comes to ease of installation and use with rock-solid security, nothing comes close to deployment of WhiteLists with the IPtables Linux firewall that’s included at no cost with every major Linux distribution and with all of the Asterisk® aggregations including PBX in a Flash™ and Incredible PBX™. So we’re kicking off the summer with a careful look at the methodology behind IPtables and the Travelin’ Man™ tools developed to reduce the learning curve for new users.
Security, of course, is all about the "bundle of sticks." As we learned from Aesop’s Fables, the more sticks you bundle together, the more difficult it is to break the stick. We are by no means advocating that you drop all of the other tools at your disposal to improve the security of your Asterisk security. So, before we dive into WhiteLists, let’s spend a little time covering some of the other tools that are available and why those tools should not be relied upon exclusively.
1. Hardware-based Firewall. The PBX in a Flash project has cautioned users for years not to run Asterisk-based servers connected to the Internet without a hardware-based firewall between your server and the public Internet. Is it failsafe? No. Some hardware-based firewalls have been compromised either by the bad guys or by the NSA. Pardon the redundancy. The other problem with hardware-based firewalls is that they’re generally not available with cloud-based solutions. As the price of cloud computing has dropped and the cost and headaches of maintaining your own hardware has increased, more and more folks are considering cloud-based alternatives. Yes. Hardware-based firewalls should be deployed whenever possible. No. They won’t resolve all security concerns.
2. Fail2Ban. Once upon a time, a number of us thought that Fail2Ban was the answer to all security issues with Asterisk-based servers. In a nutshell, Fail2Ban scans your logs searching for failed attempts to log in to either SSH, FTP, Apache, SIP, or an email account. After a small number of failed attempts, Fail2Ban blocks further access from the IP address initiating the requests. There are two problems with Fail2Ban. First, software developers of the affected services continue to "improve" things with new and different error messages when login failures occur. Since Fail2Ban is searching for specific word matches to identify unsuccessful logins, the whole security mechanism fails when the "magic words" change unless everyone is extremely vigilant in maintaining the "magic word" lists AND updating the Fail2Ban rules on all of your servers. Our experience suggests that the bad guys find the new "magic words" long before everyone else which means there are gaping holes in Fail2Ban regularly. The other problem is supercomputers such as Amazon EC2 which makes enormous computing resources available to every Tom, Dick, and Harry. We’re mostly worried about the Dick that can hammer your little server every second with hundreds of thousands of attempts to crack your SIP or SSH passwords. The problem this poses is that most Linux servers never allocate a sufficient time slice to Fail2Ban to scan your Asterisk, Apache, and SendMail logs. Instead of blocking a bad guy after 3 failed login attempts, a bad guy using EC2 may be able to perform several hundred thousand login attempts before Fail2Ban ever detects a problem. Yes. Fail2Ban helps against the bad guy manually keying in passwords. No. Fail2Ban is all but worthless against a sophisticated denial of service attack on your server.
3. Virtual Private Networks. The beauty of virtual private networks (VPNs) is that all of your Internet traffic is encrypted and tunneled through private IP addresses that others can’t intercept. That was the theory until Edward Snowden came along and spoiled the NSA’s party. Yes. We’ve known that PPTP VPNs were vulnerable for a good long while. No. We didn’t know that the NSA (and presumably others) may have had the keys to your castle much longer… regardless of the VPN topology you may be using. The other problem with VPNs is that you need VPN connections for every device connecting to your server. Unfortunately, VPN technology is only available on a small number of SIP telephones, and the supported OpenVPN topology is one of the more difficult VPNs to deploy on a Linux server. Are VPNs better than nothing? Absolutely. Does a VPN provide failsafe communications security over the open Internet? Probably not.
4. Nothing Beats Secure Passwords. Amen. There was a time when some Asterisk-based servers were routinely set up with extension passwords of 1234 or the extension number itself. And outbound SIP trunks were deployed with no dialing rules. And administrators opened accounts with SIP providers with automatic credit card replenishment whenever the accounts ran out of money to cover calls. And no safeguards were put in place to restrict international calling. Little did these folks know that registering to a SIP extension on an Asterisk server provided a blank check for making unlimited calls to anywhere on the planet. Thus was born the $100,000 phone bill. Yes. Nothing Beats Secure Passwords for root, for SIP accounts, and for SIP and IAX trunks connected to commercial providers. But you also need to implement dialing rules for outbound calls that allow your callers to reach only the destinations desired, not the world. And your accounts with providers should always include limits and restrictions on international calls and should never include automatic credit card replenishment.
5. BlackLists. There was a time when blacklisting IP addresses was believed to be the ultimate solution to Internet security problems. Sounds great, doesn’t it? Just set up a database with the IP addresses of all the bad guys in the world, and all our problems will be solved. Problem #1: A new bad guy is born every minute. Problem #2: The bad guys learned how to use VPNs and other random IP address masquerading sites to disguise their true identity. Problem #3: Security vulnerabilities in many Windows-based machines allowed the bad guys to take control of these computers and do their dirty work from there. Problem #4: There are actually some good guys that live in Russia and China. Problem #5: The bad guys learned to poison the "bad guy list" to block essential services such as DNS, Google, Amazon, Netflix, Pandora, and your favorite bank and credit card companies. Yes. The theory of blacklists sounded great. No. Blacklists not only don’t work. They’re downright dangerous.
WhiteLists with IPtables: The Knight in Shining Armor
For the past few years, our Internet security focus has turned toward defining a methodology that works with all PBX in a Flash and Incredible PBX servers, whether they’re dedicated servers behind a hardware-based firewall or public on a cloud-based shared host. And the conclusion we’ve reached is that nothing beats the IPtables Linux firewall for rock-solid Internet security. The reason is its deep integration into the Linux kernel itself through Netfilter, "a set of hooks inside the Linux kernel that allows kernel modules to register callback functions with the network stack." Wikipedia provides an excellent overview for those with an interest. For our purposes, suffice it to say that IPtables examines inbound and outbound packets before any further processing occurs on your server. With our default setup, we typically allow all outbound traffic from your server. For inbound traffic, if the iptables rules permit access, the packet comes in for processing. If not, the packet dies at the door with no acknowledgement that it was even received. In laymen’s terms, if someone attempts to scan your server to determine whether web or SIP services are available, there will be no response at all unless packets from the scanning server’s IP address are permitted in the iptables rules configured on your server. You can determine which rules are in force with this command: iptables -nL.
The basic configuration and syntax of iptables rules can be daunting to those unfamiliar with the territory. And thus was born Travelin’ Man 3, our open source tool to simplify configuration of IPtables by allowing administrators to define WhiteList entries describing the types of services that were allowed access to a server from specified external IP addresses. The basic rules of the Travelin’ Man 3 setup for iptables are these: (1) outbound packets are unrestricted, (2) forwarded, established, and related packets are permitted, (3) inbound packets from the private LAN are unrestricted, but (4) inbound packets from the public Internet are dropped unless permitted by a specific iptables rule. Those rules include certain basic services such as time synchronization (TCP 123) as well as WhiteListed IP address entries for specific or generic services.
Installation is easy. Log into your PBX in a Flash as root and issue the following commands. NOTE: Travelin’ Man 3 is optionally available as part of Incredible PBX installs on the CentOS, Scientific Linux, and PIAF OS platforms. It is preinstalled on the Raspberry Pi and BeagleBone Black platforms with RasPBX. You can determine if it’s already installed on your server with this command: ls /root/secure-iptables. If the script exists, you’ve already got Travelin’ Man installed, but it may not be running so keep reading…
cd /root
wget http://incrediblepbx.com/travelinman3.tar.gz
tar zxvf travelinman3.tar.gz
yum -y install bind-utils
./secure-iptables
Because PBX in a Flash and Incredible PBX servers are primarily designed to support telephony, Travelin’ Man 3 further simplifies the iptables setup by whitelisting the IP addresses of a number of the leading VoIP providers. These include Vitelity (outbound1.vitelity.net and inbound1.vitelity.net), Google Voice (talk.google.com), VoIP.ms (city.voip.ms), DIDforsale (209.216.2.211), CallCentric (callcentric.com), and also VoIPStreet.com (chi-out.voipstreet.com plus chi-in.voipstreet.com), Les.net (did.voip.les.net), Future-Nine, AxVoice (magnum.axvoice.com), SIP2SIP (proxy.sipthor.net), VoIPMyWay (sip.voipwelcome.com), Obivoice/Vestalink (sms.intelafone.com), Teliax, and IPkall. For the complete list: cat /etc/sysconfig/iptables (CentOS) or cat /etc/network/iptables (RasPBX).
The real beauty of Travelin’ Man 3 is you aren’t limited to our WhiteList. You can add your own entries easily using the TM3 scripts that are included in the /root directory. secure-iptables initializes your iptables setup and also lets you define a primary IP address or fully-qualified domain name (FQDN) that will always have access to your server. You must run this script at least once to activate IPtables on all platforms!
Once you have run secure-iptables, you can whitelist additional IP addresses by running add-ip. You can whitelist additional FQDNs by running add-fqdn. You can delete either IP addresses or FQDNs by running del-acct. As noted previously, you can check what’s authorized with the command: iptables -nL.
We’ve also included a custom script to restart IPtables gracefully: iptables-restart. The reason is because using the traditional restarting mechanism in IPtables will leave your server vulnerable (and IPtables inoperative) if a particular FQDN cannot be resolved. The iptables-restart script takes another approach and removes the offending rule from your whitelist, alerts you to the problem, and then restarts iptables without the offending entry. So all existing rules are put back in place and function as you would expect.
Finally, Travelin’ Man 3 includes a script that allows you to utilize FQDNs for users that may have ever-changing dynamic IP addresses. Steps #4, #5, and #6 in the original Travelin’ Man 3 tutorial will walk you through the Administrator set up which only takes a minute or two and never has to be touched again. Basically, a cron job script is employed to check for changes in the dynamic IP addresses you have identified with FQDNs. If changes are found, IPtables is restarted which updates the IP addresses accordingly.
Unfortunately, there was one group of end-users that weren’t covered by the Travelin’ Man 3 setup. This group included traveling salespeople or vacationing individuals that may land in a different city every night. Rather than relying upon an administrator to provide access to home base, these frequent travelers needed their own tool to manage their IP address as it changed. While this was supported through a web interface in Travelin’ Man 2, that setup exposed your web server to the public Internet and was burdensome for administrators to initially configure. Most importantly, it didn’t manage remote IP address access using IPtables which made coexistence with TM3 difficult. Thus was born Travelin’ Man 4.
Introducing Travelin’ Man 4: Managing WhiteList Access by Telephone
Travelin’ Man 4 is a new add-on for an existing Travelin’ Man 3 setup. It’s for those that wish to allow traveling individuals to manage their own whitelist access to PBX in a Flash or Incredible PBX using a telephone. An Administrator preconfigures accounts and passwords for the travelers together with the services to which they will have access on the server. Using any cellphone or hotel phone, the traveler simply dials a preconfigured number to access an IVR that will prompt the user for an account number and PIN. Unless you have a spare DID, you can grab a free one from IPkall.com to use with your Travelin’ Man 4 IVR. Once a user is successfully logged in, the IVR will prompt for the user’s IP address to be whitelisted on the server. Enter it using this format: 12*34*56*78.
Within a couple minutes, the new IP address will be properly formatted and then whitelisted in IPtables, and the traveler will be sent an email acknowledging that the account has been activated. Once the account is activated, the traveler can use a SIP softphone application such as Zoiper on any iPhone or Android phone or a softphone on any desktop computer to place and receive calls as well as to check voicemail on the remote PBX in a Flash server. For anyone that doesn’t know their current IP address, a quick visit to WhatIsMyIP.com will tell you. Travelin’ Man 4 is licensed under GPL2 so download a free copy. Then read the tutorial and give it a whirl. Enjoy!
Originally published: Wednesday, May 21, 2014
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