Last week, I have experienced a strange scenario with Adtran NV3448(a router) and an ISP circuit. Adtran is a similar company like Cisco, also makes networking equipment such as Router, switches, etc.
Adtran NV3448 (a router) was attached to an ISP circuit on Eth 0/2 port with a direct connection. There is a simple configuration on the Adtran with the ISP IP as a default gateway.
ISP = 192.168.1.1/29 Adtran = 192.168.1.6/29
When I perform a continuous ping from Adtran to the ISP IP, I am getting the following result.
Adtran-NV3448#ping 192.168.1.1 repeat 50 Type CTRL+C to abort. Legend: '!' = Success, '?' = Unknown host, '$' = Invalid host address '*' = Request timed out, '-' = Destination host unreachable 'x' = TTL expired in transit, 'e' = Unknown error 'B' = Packet too big Sending 50, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds: !!!!!!!!!!!!!!!!!!!!*!************************** Success rate is 43 percent (21/48), round-trip min/avg/max = 1/2/2 ms
As a part of troubleshooting, I have replaced the cable between Adtran and the ISP circuit. I have attached my laptop (192.168.1.6) to the ISP circuit and was able to ping the gateway without any issue. I attached my laptop (192.168.1.1) to Adtran Eth 0/2 port and Adtran was able to ping my laptop without any drop. Even with a different Adtran device or the port wouldn't work.
I reached out to the Carrier and they removed the firewall and Wi-Fi from their device and the issue is still pending.
Any help would be appreciated.