Just wanted to share an odd issue we had with these older Sangoma phones.
On Thurs, Oct 3rd, we got a report that an S300 kept rebooting. We thought something happened with the phone, so we swapped it out with a S305. Then the next day, we got reports of S300 having issue with bad audio, or won’t dial, etc. We would reboot and they would appear to work fine.
The following week, we had the same issue, S300s and S500 locking up or won’t dial, or stuck in a boot loop. Getting out a spare S300, we found that when it would boot up, it would show (null) and then the MAC address, rather than just MAC: . This was very odd, and of course, it wouldn’t provision. It would get stuck at Checking Firmware.
I went through various troubleshooting, including downloading different firmware, etc, but nothing seemed to fix the issue. Other models (S705, S305 and Yealinks) had no issues. However, I did find that any port that had our main VoIP VLAN mapped, would cause the S300 to lock up. If I put it on a diffferent VLAN, that didn’t have the VoIP VLAN mapped, it would boot up and work fine.
This led me to using Wireshark and I found that on the VoIP VLAN, there was an ICMPv6 multicast packet that was flooding the network. The source was a Lenovo desktop that was in sleep mode. I’m still investigating how a deskop, that was on a port that has the VoIP VLAN tagged, but itself is on a different VLAN, was flooding that network. This was only causing issues for the S300 or S500 (and assume S700) models. They must not discard the ICMPv6 (IPv6) packets, and was locking up the phone.
So for anyone that runs into their S300 or S500 phones locking up or being slow, check your network and make sure there isn’t an ICMPv6 ping flooding your VLAN.
Chris