When you are putting up or maintaining an Asterisk PBX phone system, you are probably seeking more flexibility, more control and decreased expenses. And you are most definitely making the right choice- Asterisk is one of the most potent open-source PBX systems in the market.
The thing is though that even a slight wrong configuration can result into poor call quality, call drop or even system crash!
No matter what you are, a small company, an IT administrator or managing a call center in the cloud, there are 10 reoccurring errors that should never be done when setting your PBX system to Asterisk, here they are:
1. Skipping Essential Security Settings
Problem: Many users install Asterisk and forget to secure it—leaving it vulnerable to hacking attempts.
Fix It:
Change all default passwords
Use strong, complex SIP credentials
Set IP access control (whitelisting)
Enable firewalls and tools like Fail2Ban
Maintain the up-to-date of your system
Exclusive Bonus Tip to Cloud Call Centers: Your cloud Asterisk PBX must always be guaranteed using VPNs and closing ports that are not being consumed.
2. Misconfigured NAT Settings for Remote Users
Problem: Hearing “I can hear them, but they can’t hear me?” That’s likely a NAT issue.
Fix It:
Use nat=yes or the updated NAT syntax in your SIP settings
Define externip and localnet in sip.conf
Test with different routers and firewalls
Especially important for remote or mobile agents using your PBX system.
3. Negligence of Network Quality (QoS)
Issue: VoIP is jitter sensitive, packet loss sensitive and latency sensitive.
Fix It:
enable Quality of Service (QoS) in your routers
Give traffic priority to SIP and RTP
Monitor bandwidth usage regularly
Split your voice and data networks where possible
In either case, the on-premise PBX and hosted VoIP, sub-par internal networking can be the murderer of call quality.
4. No SIP Trunk Failover Routes
Problem: If your SIP trunk provider goes down, so do your calls.
Fix It:
Always set up backup SIP trunks
Use failover logic in your dialplan (Dial(), GotoIf, etc.)
Monitor SIP trunk health using qualify=yes
Business continuity availability is guaranteed through provision of a powerful failover system.
5. Overcomplicated Dialplans
Issue: Asterisk offers flexibility--and you can get into too much of it and it makes your dialplan the Gordian knot of debugging.
Fix It:
This maintenance - keep dialplans clear, modular and well-commented
Use #include to organize dialplan contexts
Name effectively according to conventions and label macros effectively
Clean dialplans Pro Tip: Give it a scrubbing, then stop to find problems later: you might save hours in troubleshooting - particularly on high-traffic hosted Asterisk systems.
6. Leaving SIP Ports Open to the World
Problem: Exposing your SIP ports without restrictions can invite hackers.
Fix It:
Only open relevant ports (most often this is 5060 SIP)
Limit access to trusted IP addresses
Use VPN for secure remote access
This is critical for cloud-based PBX servers that are always online.
7. Incorrect Time Zone or System Time
Problem: Call logs, recordings, and reports get messy if your server’s clock is wrong.
Fix It:
Set your server’s time zone correctly
Enable NTP time sync
Check CDR and log timestamps during debugging
Accurate time is vital for call tracking and compliance, especially in contact center PBX setups.
8. Forgetting to Reload After Changes
Problem: Made changes to the config, but nothing works? You probably forgot to reload Asterisk.
Fix It:
Use asterisk -rx "reload" after config edits
Find monitor logs as /var/log/asterisk/
The changes become operational at the reload, so never forget to reload!
Asterisk PBX will provide professional-grade communications capability, but it has to be set up right. It is easy to make these errors, yet some forethinking and prior planning help to avoid them.
9. Not Testing Before Going Live
Problem: Launching without proper testing leads to panic and user complaints.
Fix It:
Test each function incrementally
Use internal test numbers to simulate flows
Get feedback from a test user group
Just like shifting from on-premise PBX to cloud, testing ensures a smooth transition.
10. No Backup Strategy in Place
Problem: One wrong command or system crash could erase everything.
Fix It:
Automate daily backups of /etc/asterisk/
Store backups in a separate location or cloud
Keep a changelog for easy restoration
If you’re running a cloud contact center, automate and encrypt your backups—it's worth it.
Final Thoughts: Avoiding Mistakes = Smooth Communication
Asterisk PBX offers enterprise-grade communication power—but only when configured correctly. These mistakes are common, but easily avoidable with a little foresight and planning.
By following best practices for VoIP PBX setup, using secure configurations, and thinking ahead, you can build a system that’s powerful, flexible, and rock-solid.
