As system administrator, monitoring the continuity of services is vital. Today I would like to highlight some tools that could come in handy for VoIP monitoring.NagiosFor those of you who didnt know it, Nagios can be configured to monitor pretty m..
The flowroute website mentions that they set callerid on outbound calls based on the presence of (in order of preference):P-Asserted-Identity, Remote-Party-ID..
To put it simply, is the process where Asterisk tries to redirect the RTP media stream to go directly from the caller to the callee. Be careful that some devices do not support this (especially if one of them is behind a NAT). The default setting..
If you were asking if E&M over E1 signalling works on top of R2, ISDN and where can you find a sample Dahdi configuration? Then, no it doesn’t. E&M signalling is the same layer as R2 and ISDN. It is an alternative to them, not anot..
Decrementing the CSeq header field value is directly in violation of RFC 3261. From section 22.2: When a UAC resubmits a request with its credentials after receiving a 401 (Unauthorized) or 407 (Proxy Authentication Required) response, it M..
After re/starting Asterisk with a user other than root you might see this error:/usr/sbin/safe_asterisk: line 86: ulimit: open files: cannot modify limit: Operation not permitted,even if you try to set the current ulimit to a higher level.Edit y..
What should I do in order to to be as secure as possible and with “clean” logs?Well, for an article about Asterisk security best practices, consider reading this article.About SIP and NAT best practices, in short, the simplest answer is to alw..
If you were wondering about the correct format of US numbers then this might come in handy. In short: The proper way to send CallerID number is 10 digit (from NANPA numbers), no preceding 1 or plus sign (+) as this is handled by the provider to the ..
If after installing Asterisk 10.X.X you see the following errors on SIP reload: No valid Transports Available, Falling Back To UDP, This might be because a possible regression. Please open an issue in JIRA referencing th..
Due to high volume of outbound calls you might be asked to alternate the outbound traffic by your termination provider.Basically, what what you need to do here is: Having 2 destinations (Dst_A, Dst_B), check/set a variable in the AstDB. Then if the varia..