DataGuard ORA-07286: sksagdi: cannot obtain device information.

主库查询
show parameter dest;
set lines 200 pages 50000
select dest_id,error from v$archive_dest;
select dest_id,status,error from v$archive_dest_status where dest_id=2;
select dest_id,status,error from v$archive_dest where dest_id=2;

重启备库
shutdown immediate;
startup nomount;
alter database mount;
alter database open read only;
alter pluggable database all open read only;
alter database recover managed standby database cancel;
alter database recover managed standby database using current logfile disconnect from session;

重启通道
alter system set log_archive_dest_state_2=defer scope=memory sid='*';
alter system set log_archive_dest_state_2=enable scope=memory sid='*';
alter system switch logfile;
alter system switch logfile;
alter system switch logfile;
select error,status from gv$archive_dest where dest_id=2;