The situation is there are two sites which using UCM6510 pabx where i named it as site A (KPC) and site B (NDWT). The problem is Site A can peer with site B but site B cannot peer with site A. After hundreds of time checking, there is no differences in term of config between site A and site B. The funny things is site B can ping and tracert to the site A.
Is there any suggestion or recommendation for troubleshooting?