生产库的备库在做rman备份到磁带的时候，总是失败。
查找原因时发现：
crosscheck archivelog all;
delete noprompt expired archivelog all;
##allocate channel for maintenance type 'sbt_tape';
crosscheck backup;
crosscheck copy;
delete noprompt expired backup;
delete noprompt expired copy;
delete noprompt obsolete;
for maintenance 关键字在run{}中执行时会报错
下面介绍一下
ALLOCATE CHANNEL FOR MAINTENANCE命令。
ALLOCATE CHANNEL FOR MAINTENANCE命令是用来分配通道的，专用于CHANGE、DELETE、CROSSCHECK命令，并且也不需要（而且也不能）包含在RUN块中。
默认配置下CONFIGURE已经分配了一个指定 DISK 的通道，因此也可以不需要执行ALLOCATE CHANNEL FOR MAINTENANCE命令，Oracle也建议通过CONFIGURE分配通道，来替代使用该命令维护管理用的专用通道，这可能会增强备份脚本的复杂度。
=================================metalink 官方文档解释======================================
RMAN Run Allocate Channel For Maintenance From Script. Fails With Syntax Error [ID 224353.1]
fact: Oracle Server - Enterprise Edition
fact: Recovery Manager (RMAN)
symptom: Allocate Channel For Maintenance fails
symptom: RMAN-01005: syntax error: found "for": expecting one of:
"channel_id, double-quoted-string, identifier, single-quoted-string"
symptom: RMAN-01007: at line %d column %d file: %s
symptom: allocate channel for maintenance type disk;
原因： Cannot Run RMAN Allocate Channel For Maintenance From An RMAN Script.
Must Be Run Direct From The RMAN Prompt.
现象：
Running the following will fail.
RMAN> run {
3> allocate channel for maintenance type disk;
执行报错~~~！
解决：
Run direct from RMAN prompt.
RMAN> allocate channel for maintenance type disk;
RMAN> crosscheck backup of database;
=========================测试例子如下=====================
测试环境：
oracle版本:11.2.0.1.0
rman 版本:11.2.0.1.0
=========================二备库=======================
正确的方式：
RMAN> run {
2> allocate channel ch00 type 'SBT_TAPE';
3> RELEASE CHANNEL ch00;
4> }
allocated channel: ch00
channel ch00: SID=678 device type=SBT_TAPE
channel ch00: Veritas NetBackup for Oracle - Release 6.5 (2010042404)
released channel: ch00
RMAN>
错误的方式：
RMAN> run {
2> allocate channel ch00 for maintenance type 'sbt_tape';
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found "for": expecting one of: "device, type"
RMAN-01007: at line 2 column 23 file: standard input
=====================rac测试环境 =========================
--------------------下面是错误的例子-------------------------
RMAN> run {
2> allocate channel ch00 for maintenance type disk;
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found "for": expecting one of: "device, type"
RMAN-01007: at line 2 column 23 file: standard input
RMAN> run {
2> allocate channel ch00 for maintenance device type disk;
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found "for": expecting one of: "device, type"
RMAN-01007: at line 2 column 23 file: standard input
RMAN> run {
2> allocate channel ch00 for type disk;
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found "for": expecting one of: "device, type"
RMAN-01007: at line 2 column 23 file: standard input
RMAN> allocate channel ch00 device type disk for maintenance;
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found "identifier": expecting one of: "for"
RMAN-01008: the bad identifier was: ch00
RMAN-01007: at line 1 column 18 file: standard input
RMAN> run {
2> ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE DISK;
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found "for": expecting one of: "channel_id, double-quoted-string, identifier, single-quoted-string, "
RMAN-01007: at line 2 column 18 file: standard input
RMAN> run {
2> allocate channel ch00 device type disk ;
3> release channel;
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00558: error encountered while parsing input commands
RMAN-01009: syntax error: found ";": expecting one of: "channel_id, double-quoted-string, identifier, single-quoted-string, "
RMAN-01007: at line 3 column 16 file: standard input
--------------------下面是正确的例子-------------------------
RMAN> ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE DISK;
allocated channel: ORA_MAINT_DISK_1
channel ORA_MAINT_DISK_1: SID=963 instance=rac1 device type=DISK
RMAN> release channel;
released channel: ORA_MAINT_DISK_1
RMAN> run {
2> allocate channel ch00 device type disk ;
3> release channel ch00;
4> }
allocated channel: ch00
channel ch00: SID=963 instance=rac1 device type=DISK
released channel: ch00
RMAN>
