[root@rusky2 mnt]# mount /dev/cdrom /mnt/cdrom mount: block device /dev/cdrom is write-protected, mounting read-only[root@rusky2 mnt]# mount -o ro  /dev/cdrom /mnt/cdrom     #-o rw 用可读写模式挂载mount: /dev/cdrom already mounted or /mnt/cdrom busymount: according to mtab, /dev/hdc is already mounted on /mnt/cdrom[root@rusky2 mnt]# ls /mnt/cdromCluster         README-en       README-ml.html     README-zh_TW.html      RELEASE-NOTES-it.html     RELEASE-NOTES-si.html         RPM-GPG-KEY-redhat-releaseClusterStorage  README-en.html  README-mr.html     RELEASE-NOTES-as.html  RELEASE-NOTES-ja.html     RELEASE-NOTES-ta.html         ServerEULA            README-es.html  README-or.html     RELEASE-NOTES-bn.html  RELEASE-NOTES-kn.html     RELEASE-NOTES-te.html         TRANS.TBLeula.en_US      README-fr.html  README-pa.html     RELEASE-NOTES-de.html  RELEASE-NOTES-ko.html     RELEASE-NOTES-zh_CN.html      VTGPL             README-gu.html  README-pt_BR.html  RELEASE-NOTES-en       RELEASE-NOTES-ml.html     RELEASE-NOTES-zh_TW.htmlimages          README-hi.html  README-ru.html     RELEASE-NOTES-en.html  RELEASE-NOTES-mr.html     RPM-GPG-KEY-fedoraisolinux        README-it.html  README-si.html     RELEASE-NOTES-es.html  RELEASE-NOTES-or.html     RPM-GPG-KEY-fedora-testREADME-as.html  README-ja.html  README-ta.html     RELEASE-NOTES-fr.html  RELEASE-NOTES-pa.html     RPM-GPG-KEY-redhat-auxiliaryREADME-bn.html  README-kn.html  README-te.html     RELEASE-NOTES-gu.html  RELEASE-NOTES-pt_BR.html  RPM-GPG-KEY-redhat-betaREADME-de.html  README-ko.html  README-zh_CN.html  RELEASE-NOTES-hi.html  RELEASE-NOTES-ru.html     RPM-GPG-KEY-redhat-former