两天碰到两起类似事件

昨天的情况是 一套物理备库 备库alert显示于1月3号同主库的连接终止，从那之后再也没有接受到归档日志；

登陆主库，发现tnsping备库可以连通，log_archive_dest_n_2为enable； 备库的监听器正常工作，且v$archive_gap没有记录； 使用的是arch模式传输；

后来经过一系列调试，尝试增大主库的log_archive_max_processes值，由2加大到4，然后问题解决了

对此，metalink上有篇相关的文章。

今天又是同样的问题，不同的是主库是两节点RAC，其中一个节点的日志可以正常传输，另一个死活不行；两个节点的配置是一样的，加大log_archive_max_processes，由2到6，该节点还是无法传输日志到备库；

最后只能手工传输并发现了问题，原来出问题的节点与备库之间的网络出现问题，scp时候只传输1秒就会断开，难怪日志一直无法传输到备库。

In this Document
  Symptoms
  Cause
  Solution
  References

Applies to:

Oracle Server - Enterprise Edition - Version: 10.2.0.1 to 10.2.0.3
This problem can occur on any platform.

Symptoms

In a Data Guard Configuration, during Scheduled RMAN Backup no Redo is transported to the Standby Server as the ARCH Process is blocked (as expected ie. RMAN would utilize 1 ARCn Process and the other ARCn for local Archiving ) which means the Standby stays out of sync (assuming max_arch_processes=2) until the ArchiveLog is manually copied across and registered to the Standby Database after which the Standby Database resumes applying the ArchiveLogs .

Standby alert log: 
RFS[28]: Assigned to RFS process 4092 
.... 
Fri Nov 09 16:24:48 2007 
RFS[28]: Possible network disconnect with primary database 

 Primary alert log: 
LNS1 started with pid=20, OS id=6020 
.... 
Fri Nov 09 16:26:17 2007 
Committing creation of archivelog 
'E:\ORADATA\EMPOWER\ARCH\ARC10374_0619028071.001' 
Failed to send message to ARCH process (function = 0xa) 
LNS1 started with pid=20, OS id=2800

Cause

All RFS disconnects are caused by the Death of their associated LNS Process .

The Primary does not have enough ARCn Processes. that one has got stuck for some Reason leaving no other ARCn Processes to ship FAL Requests (One ARCH only serves LOCAL destinations).

Also if an ARCn-Process gets stuck, you can simply kill it using an OS-Kill. This has no Impact on the Database itself since the PMON-Process will restart it automatically

Solution

Please ensure you set the LOG_ARCHIVE_MAX_PROCESSES Initialization Parameter at least to the recommended Value of 4 when using a Data Guard Configuration, depending on the Setup even more Archive Processes might be required.