oracle异地备库出现自动kill进程的情况？

环境:红帽6.9+oracle 11.2.0.4

目前架构：一主两备。一个同机房备库、一个异地备库

背景：添加异地备库后，发现异地备库的传输路径进程经常自动kill掉

主库错误信息:

WARN: ARC2: Terminating pid 1016 hung on an I/O operation
Killing 1 processes with pids 1016 (Process by index) in order to remove hung processes. Requested by OS process 6318

异地备库错误信息：

WARN: ARCH: Terminating pid 29649 hung on an I/O operation
Killing 1 processes with pids 29649 (Process by index) in order to remove hung processes. Requested by OS process 25490

异地备库传输路径参数

log_archive_dest_3： SERVICE=lmdg2 LGWR ASYNC   noaffirm VALID_FOR=(ONLINE_LO GFILES,primary_ROLE) DB_UNIQUE _NAME=lmdg2

求助各位大佬