use Customize ports on 3cx pbx & genatic sip access outside local network

[guru2gr8]

Hello 3cx expert, I need little help to configure my 3cx pbx.

I have installed 3cx on virtual google cloud machine on debian stretch. At the time of installation I use customize ports 5000 >45000, 5001 >45001, 5060>45060, 5090>45090. After installation I accessed my pbx via web page https://my.ip.address:45001. I have configures VOIP.ms sip trunk & install 3cx on my android phone. I am able to receive incoming & outgoing on 3cx android app. So everything working proper upto this step.
Now I want to configure my Linksys SIP phone adapter with 3cx genetic sip extension. But this thing is not working. I have put these variable in Linksys ata
In LINE 1
Line Enable: yes
Nat Mapping Enable: yes
NAT keep alive dest: yes
Proxy: public ip of cloud 3cx
Register: yes
Make call without reg: no
Ans call without reg: no
Display name: 200 (ext. #)
User ID: 200
password: xxxxxxx (password set in extension on 3cx)
Use Auth ID: yes
Auth ID: xxxxxxx (user id set in extension on 3cx)
Under Audio configuration for Line 1
Preferred Codec: G711u
Linksys ata still not able to register the 3cx cloud pbx.
So I start troubleshooting
Also in google firewall I configured firewall according to new defined ports.
On cloud linux machine I try to check iptable settings by giving following commands & result
>>sudo iptables -L INPUT --line-numbers | grep -e 5060 -e 50902 ACCEPT tcp -- anywhere anywhere multiport dports 45000,45001,45060,45061,45090 tcp flags:FIN,SYN,RST,ACK/SYN ctstate NEW3 ACCEPT udp -- anywhere anywhere multiport dports 45060,45090
>> sudo iptables -S INPUT | grep -e 5060 -e 5090-A INPUT -p tcp -m multiport --dports 45000,45001,45060,45061,45090 -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -m conntrack --ctstate NEW -j ACCEPT-A INPUT -p udp -m multiport --dports 45060,45090 -j ACCEPT
So iptable looks OK to me.
Is someone help me & guide me to make system work properly. Is I have problem in cloud pbx side or something wrong in my home network Linksys ATA side.

thanks

 

[guru2gr8]

3cx firewall check result is as shown

 

[complex1]

Because you use a non standard SIP port (45060) you need to add the port number in the Proxy field
Proxy: public ip of cloud 3cx:45060

 

[BrenttG]

Also, i feel compelled to tell you this because i have a feeling you moved those ports around for security reasons yes?

Moving those ports to the high range with the idea that hackers will not find them is a bad philosophy because any basic port scan will identify them instantly and allow hackers to try to attack the system.

Moving the ports for preference is one thing, but if you did this particularly for security reasons, just know that relying on this as the main part of a security plan is absolutely bad practice, and you should still employ a proper firewall and good security practices.

 

[guru2gr8]

thanks Complex1, you are absolutely right. when i write port number in proxy with web address:45060. system able to register & system works fine. just for clarification on top part linksys ATA SIP port: tab i have to write 5060 or 45060 there. this time i have write 45060. which number is preferable there 5060 or 45060 or nothing (erased everything)