�
What are reasons for VDSL2 synchronization failure (also referred as
link down or link establishment failure)?
If the VDSL2 suddenly fails to be synchronized (link down) during applica-
tion, usually the Link indicator on the ZXHN H268N will not be ON. It is
suggested to check the following steps one by one:
i. First check the quality of incoming cables and incoming cable connectors.
ii. Install the ZXHN H268N correctly based on the user guidance. Minimize
the number of taps.
iii. Check whether the telephone cables and VDSL2 are in good connection
or whether the telephone cables are normal.
iv. Try to disconnect the splitter and directly connect the ZXHN H268N to the
incoming user cable end. Ensure the problem is not due to improper in-
stallation or incoming user line quality. If the VDSL2 can be synchronized
again, it means that installation of the incoming user side is improper.
Please reinstall it according to the user guide.
v. If the VDSL2 still fails to be synchronized when the ZXHN H268N is con-
nected to the incoming user cable end, contact the operators to check
whether it is due to external line failure or ZXHN H268N failure.
vi. If the splitter problem is determined, call the operator for maintenance or
replacement.
vii. If the problem is due to the end office equipment failure, call the operator
to confirm it.
viii. Too long connection cable between the splitter and ZXHN H268N may
cause poor anti-interference performance and synchronization difficulty.
Therefore, the connection cable should not be too long.
