从报错来看，应该是在做crosscheck的时候报的错，请提供下完整的备份语句。

这是一个Oracle BUG：

Bug 28432129 - RMAN-06091: no channel allocated for maintenance (of an appropriate type) after installing July 2018 (DBPSU/BP/RU) (文档 ID 28432129.8)

参考上面文档中的Workaround部分处理

Workaround :
Explicitly allocate a disk channel.

Example :
 RMAN> allocate channel for maintenance device type disk;
 RMAN> crosscheck archivelog all;

或者，将delete 命令从run {} 命令块中移到外面来，也可以解决。

rman>connect target *

configure channel device type 'sbt_tape' clear;

configure backup optimization off;

run {

allocate channel ch1 device type sbt maxpiecesize=30G;

sent 'ENV=(connect_tag=xxx)';

backup incremental level 0 database format 'ordb_%d_%s_%p_%t' tag '2019_06_04_11_12_16';

release channel ch1;

}

run {

allocate channel ch1 device type sbt maxpiecesize=30g；

sent 'ENV=(connect_tag=xxx)';

crosscheck archivelog all;

backup archivelog from toem 'sysdate-3' format 'arch_%d_%s_%p_%t' tag '2019_06_04_11_12_16';

release channel ch1;

}

run {

allocate channel ch1 device type sbt maxpiecesize=30g；

sent 'ENV=(connect_tag=xxx)';

backup current controlfile format 'ctrl_%d_%s_%p_%t' tag '2019_06_04_11_12_16';

delete archivelog all completed before 'sysdate-5';

release channel ch1;

}

谢谢各位老师，我打了p28432129_11204180717_Linux-x86-64.zip这个补丁，问题