We have tow customer (A&B) they are using Huawei NGSDH equiment and there is interconnection between them through STM-1(O). one day the operation engineer of company A he was working to do some configration in one NE (OSN 7500) but the result was error, he upload the NE but NE was changed from OSN 7500 to OSN 2500 and also he observed that som NEs not login
1- checked if there is another user did any change we found no
2- checked the ECC it was OK
3- Changed OSN 2500 to another NE ID and upload OSN 7500 it was Ok but still there were some NEs not login
4- I was remeber there is interconnection with other customer and I thought may be the ECC is opened, after checked I found the ECC is opened between A&B in one STM-1, after closed the ECC all NEs was ok and login in NMS.
1- ECC problem
2- another user make change
Must close the ECC if there two customer or more use Huawei SDH and have interconnection betwen them