while comissioning an ASON ROADM node the OPA function fails to preset on this node.
this node have two local dimenssions and three directions (A,B and C) to three different sites. the local dimenssion have the OTU and the Line and tributary unit . the picture below shows the WSS which contains the ROADM boards (RDU9 + WSM9) and how they are connected in this node.
we use two equpiment OSN 6800 as Optical NE and OSN 8800 as electrical NE the version used is V1R5SPC900 for both equipments.
No alarm was related to this problem in U2000, but the report in the MDS6630 software give us fail result in some parts of the comissioning.
In order to invetigate the problem we reviewed the signal flow on U2000 every thing was ok.
after that we made the cross-connection also it succeded so no software problem then we start to review the internal fiber design . the original design is as follows.
after checking all connection we found one mistake during installation, that the fibers from WSM9 to RDU9 were reveresed so now (WSM9 expi port is connected to the other WSM9 AM3) and (RDU9 expo is connected to the other RDU9 DM3 port).
so the connection was changed and preset again the OPA by MDS 6630 and all the lambdas in all direction were preseted succesfuly without any error.
when the OPA preseting finished the report have some points not succes.
after that we check these failed part so its concluded that 6 lambdas faild to be preset in specific direction which is from Local 1 to Direction C.
The illustration belows identify the part that have problem.
Always a double check should be performed on the installation to avoid a problem of this kind.