往磁带先后TAR两个目录第一成功，第二个不成功，高手帮我看看

apache2

在SOLARIS9上用两个TAR命令往磁带上备份目录，第一个没什么问题，但是第二个命令输出信息正常，但是文件根本没到磁带上，这是怎么回事，下面是执行的命令和输出结果，大家帮忙看看
root@hist # mt -f /dev/rmt/0 rew
root@hist # tar cvf /dev/rmt/0cn tartest
a tartest/ 0 tape blocks
a tartest/arc00000037622.0001 20477 tape blocks
a tartest/arc00000037623.0001 20477 tape blocks
a tartest/arc00000037624.0001 20477 tape blocks
a tartest/arc00000037625.0001 20477 tape blocks
a tartest/arc00000037626.0001 20477 tape blocks
a tartest/arc00000037627.0001 20477 tape blocks
root@hist # tar cvf /dev/rmt/0cn tartest111
a tartest111/ 0 tape blocks
a tartest111/devp.ctl 31 tape blocks
a tartest111/devp.ctl20070522 31 tape blocks
root@hist # tar tvf /dev/rmt/0
tar: blocksize = 0
root@hist # mt -f /dev/rmt/0 rew
root@hist # tar tvf /dev/rmt/0
drwxr-xr-x 1001/102      0 May 29 09:27 2007 tartest/
-rwxr-xr-x 1001/102 10484224 May 29 09:27 2007 tartest/arc00000037622.0001
-rwxr-xr-x 1001/102 10484224 May 29 09:27 2007 tartest/arc00000037623.0001
-rwxr-xr-x 1001/102 10484224 May 29 09:27 2007 tartest/arc00000037624.0001
-rwxr-xr-x 1001/102 10484224 May 29 09:27 2007 tartest/arc00000037625.0001
-rwxr-xr-x 1001/102 10484224 May 29 09:27 2007 tartest/arc00000037626.0001
-rwxr-xr-x 1001/102 10484224 May 29 09:27 2007 tartest/arc00000037627.0001

apache2

参考了http://bbs.chinaunix.net/viewthread.php?tid=276742

race

需要跳过第一次备份的才能看见。 使用mt的fsf选项

yhongy

第一次饶到前面后再读带和写带时都加上n就不会出错了,哈哈