TNS-12547,TNS-12537錯誤解決方法一例

       上次在公司幫開發部裝好linux redhat as 4 update 4 64位作業系統後,並且安裝完oracle 資料庫

,補丁也已經升級到10.2.04. 客戶端訪問不了 TNS-12547: TNS：丟失連線錯誤,linux上的防火牆也已經關閉

以為是還有哪個包沒安裝齊全,然後就打掉作業系統重新安裝作業系統和資料庫,裝好後

客戶端還是訪問不了 報TNS-12537: TNS：連線關閉錯誤,監聽日誌報TNS-12525: TNS: 監聽程式在允許時間內未接收到客戶機請求

可以說還是同樣錯誤,想了很多方法去試,還是不行

最後在metalink上查到一篇文章,說可能還是防火牆問題

New Connections Intermittently Rejected with TNS-12525

Applies to:
Oracle Net Services - Version: 10.2.0.1.0 to 11.1.0.6.0
This problem can occur on any platform.

Symptoms
At regular intervals (every three hours), you see new connections rejected with TNS-12525 "listener has not received client's request in time allowed".

The listener log shows the following error stack :

10-APR-2008 17:39:15 * * (ADDRESS=(PROTOCOL=tcp)(HOST=10.221.50.31)(PORT=4184)) * establish * * 12525
  TNS-12525: TNS:listener has not received client's request in time allowed
    TNS-12535: TNS:operation timed out
      TNS-12606: TNS: Application timeout occurred

At the same time the firewall log reports :

"TCP packet out of state: First packet isn't SYN; tcp_flags: PUSH-ACK"

Wireshark (Ethereal) traces show the TCP 3-way handshake never completes for those connections.

Changes
Value of idle timer was recently changed at firewall level.

Cause
Firewall closes ports not allowing the 3-way handshake to complete at TCP level.

Solution
Increase the firewall's idle timeout interval.

 

可能還是公司防火牆問題,所以就找了單獨一臺交換機,就接伺服器和我自己電腦做測試,

測試ok ,這個問題搞了幾天了,剛開始想到是防火牆問題,只想到linux自身上的防火牆,沒想到

公司自己網路防火牆問題,差點就放棄了,不過還是貴在堅持,查資料,尋求幫助等,終於解決了

套用士兵突擊許三多說的一句話:不拋棄,不放棄。