Zabbix with Asterisk or Monitor by 2N5 for telephony monitoring?
Choose Zabbix if you want free, open-source monitoring for your entire infrastructure, including Asterisk's status, and have a team to maintain it. Choose Monitor if you need to know whether each SIP trunk or 0800 number completes calls with clear voice, without building and maintaining the test calls yourself.
Monitor by 2N5 and Zabbix, side by side
| Feature | Monitor by 2N5 | Zabbix |
|---|---|---|
| Places real test calls | Yes: calls SIP trunks, 0800, 0300, 4004 and landline numbers, the way a customer calls | No, in the official template: Asterisk by HTTP reads the Asterisk Manager API (channels, calls, queues, peers and trunks) and places no test calls (source) |
| How it measures voice quality | MOS-LQO measured on the received audio, against the reference recording (ViSQOL) | None in the Asterisk template: no MOS and no audio (source) |
| Confirms the failure before alerting | Yes: it repeats the call, and only four failures in a row by default (the first plus three retries) open an incident | Yes: trigger functions over a period, where the condition must hold for the whole window (source) |
| How it alerts and escalates | Email and SMS, in tiers, until someone acknowledges | Email, SMS, script and webhook; escalation in steps of at least 60 s, which can depend on the problem not yet being acknowledged (source) |
| SLA report | Yes: every month, with availability for the month and for the last 12 months | Yes: SLA with a target (SLO) and daily, weekly, monthly, quarterly and yearly periods (source) |
| In Portuguese | Yes: product, alerts and reports in Portuguese and English | Yes: a Brazilian website and documentation in Portuguese; pt_BR translation of the interface: not confirmed (source) |
| Managed service or do it yourself | Managed service: 2N5 registers, verifies and configures every circuit | Do it yourself: self-hosted open source; Zabbix Cloud, support, professional services and training are available for a fee (source) |
| Published pricing | No: a proposal after the demo | Free, open-source software (AGPLv3 since 7.0); support and Zabbix Cloud pricing: not confirmed (source) |
| Coverage in Brazil | Yes: 0800, 0300, 4004 and landline numbers, with any carrier; SLA measured over the year, as Brazilian contracts do | Not applicable: it is self-hosted and the Asterisk template places no calls (source) |
Where Zabbix is better
- It is free and open source, and stays entirely under your control.
- It monitors everything, servers, network and applications, not just telephony.
- It has a strong escalation and SLA engine, with steps that depend on acknowledgment and reports from a day to a year.
- It also alerts by script and webhook, so the alert can be wired to any other tool.
- It has a large community, a Brazilian website and documentation in Portuguese.
Can Zabbix tell whether Asterisk is completing calls?
Not with the official template. Asterisk by HTTP queries the Asterisk Manager API and shows active channels and calls, queues, the status of SIP, PJSIP and IAX peers, and trunk channels. It is a snapshot of what Asterisk knows about itself. The template places no test calls and does not measure the voice.
Monitor calls each SIP trunk, 0800, 0300, 4004 or landline number, the way a customer calls, and checks whether the call completed, whether audio flowed in both directions, and whether the right party answered. A peer can show as registered while callers hear silence. See SIP trunk monitoring and what a SIP registration is.
What does Zabbix do better?
It is free, open source, and monitors everything, not just telephony. Its alerting engine is strong: triggers that require the condition to hold for a whole window, escalation in steps that can depend on nobody having acknowledged the problem, and SLA with reports from a day to a year. It has a Brazilian website, documentation in Portuguese, and full control for anyone with a team to maintain it.
What if I place the test calls with a script on Asterisk?
You can get started, but the script is the easy part. Asterisk places a call when a call file is dropped into /var/spool/asterisk/outgoing/, and the AMI Originate action generates a call whose result comes back as an OriginateResponse event. A cron job firing one of those two is the usual route.
What is left to you:
- Deciding whether it passed. Answering is not the same as having audio in both directions or the right message.
- Retrying before alerting. In call files,
MaxRetriesdefaults to 0, and a retry is not a “four failures in a row” rule. - Measuring the voice. Asterisk’s own measure,
rxmes, comes from RTP RTT, jitter and loss, not from the audio compared against a recording. - Escalating, keeping the history and producing the SLA, and maintaining all of it when whoever wrote the script leaves.
The license costs next to nothing, but you still need a SIP account or trunk to dial out on and someone who knows Asterisk.
How does Monitor handle those parts?
As a managed service. 2N5 registers each circuit, proves it with a real call, and records the reference greeting. Every call is judged: did it complete, was there audio in both directions, the right message, and the MOS-LQO measured with ViSQOL. A call that fails is repeated, and only consecutive failures, four by default, open an incident with the SIP code and the Q.850 cause. The incident escalates by email and SMS, tier by tier, until someone acknowledges. See alerts and escalation and how it works.
What about SLA reports?
Both have them. Zabbix calculates SLA with a target and periods from daily to yearly, from what it monitors. Monitor sends a report every month with availability for the month and for the last 12 months, measured by the test calls, with the incidents and the time until someone took ownership. See SLA reports.
How much does each one cost?
Zabbix is free; support and Zabbix Cloud pricing were not confirmed on the pages we read. Monitor has no list price: 2N5 sends a proposal after a demo on your own numbers. See how to buy and other comparisons.
Facts about Zabbix, with sources
- The official Asterisk by HTTP template collects metrics by remotely querying the Asterisk Manager API with an HTTP agent. Source
- In Zabbix, each escalation step has a duration, with a minimum of 60 seconds, and a step can depend on the problem not having been acknowledged. Source
- Zabbix SLA has a percentage target (SLO) and daily, weekly, monthly, quarterly and yearly periods. Source
- Zabbix is distributed under the AGPLv3 license from version 7.0 on; up to 6.4, under GPLv2. Source
- In Asterisk, a call file placed in /var/spool/asterisk/outgoing/ generates a call; MaxRetries defaults to 0, RetryTime to 300 s and WaitTime to 45 s. Source
- Asterisk's own quality measure, CHANNEL's rxmes, is calculated from the RTT, jitter and loss of the received RTP stream, not from the audio. Source
Each fact above was read at the source shown on October 7, 2026 and is checked again every quarter; a change shows up here with the new date.
Frequently asked questions
Does Zabbix monitor Asterisk?
Yes. The official Asterisk by HTTP template reads the Asterisk Manager API and shows active channels and calls, queues, the status of SIP, PJSIP and IAX peers, and trunk channels. It shows what Asterisk reports about itself; it does not place test calls or measure the voice. For that, you need a call coming in from outside.
Can I place test calls with a script on Asterisk?
Yes. A call file in /var/spool/asterisk/outgoing/ or an AMI Originate action, fired by a cron job, generates the call. The rest is up to you: deciding whether the call passed, retrying before declaring a failure, escalating until someone takes ownership, keeping the history, building the SLA report, and maintaining it all when whoever wrote the script leaves.
Can Zabbix and Monitor be used together?
Yes. Zabbix keeps watching the servers, the network and Asterisk's status, and Monitor calls each voice circuit the way a customer does, notifying the escalation ladder by email and SMS. Because it calls numbers, it works with any PBX and carrier, without depending on what Asterisk reports.