Techdata VINA 지식 공유

고가용성을 위한 Gigabit Switch 권장

1) Cross-Cabling 은 2 노드 이상 확장 시 제한을 받음

2) Cross-Cabling 으로 구성시 NIC(network interface card) 가 불안정해지면 노드간의 통신이 단절되어 불규칙하게 DB instance 장애가 발생되거나  데이터 누수(Loss)가 발생되는 현상이 보고 되어 있음 (근거문서 참조.)

근거문서1. Oracle® Database Oracle Cluster ware and Oracle Real Application Clusters Administration and Deployment Guide10g Release 2 (10.2) 메뉴얼에도  다음과 같이 unsupport 한다고 설명하고 있습니다.

 1  Introduction to Oracle Clusterware and Oracle Real Application Clusters
   -  The Oracle Clusterware Architecture and Oracle Clusterware Processing
      Oracle recommends that you configure a redundant interconnect to prevent the  interconnect  from being a single point of failure. Oracle also recommends that you use User Datagram Protocol (UDP) on a Gigabit Ethernet for your cluster interconnect. Crossover cables are not supported for use with the Oracle Cluster ware or RAC databases

근거문서2. Oracle Metalink - Note 220970.1

RAC Frequently Asked Questions 으로 Crossover Cable은 지원되지 않는다고 명시되어 있습니다.

Q> Is crossover cable supported as an interconnect with 9iRAC/10gRAC on any platform ?

A> NO. CROSS OVER CABLES ARE NOT SUPPORTED.

The requirement is to use a switch:  

  Detailed Reasons:

    1) cross-cabling limits the expansion of RAC to two nodes

    2) cross-cabling is unstable:

       a) Some NIC cards do not work properly with it.

       b) Instability.  We have seen different problems

         e.g.ORA-29740 at configurations using crossover cable, and other errors.

  Due to the benefits and stability provided by a switch,

  and their afforability, this is the only supported configuration.