hunter@HP:/home/hunter #exp userid=system/yxyup wner=hunter file='/ehirearch/hunter/exp_test/hunter.dmp' log='/ehirearch/hunter/exp_test/hunter.log' direct=y  recordlength=65535 feedback=10000 statistics=none compress=N

Export: Release 10.2.0.3.0 - Production on Mon Oct 22 16:04:23 2007

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

EXP-00056: ORACLE error 1034 encountered
ORA-01034: ORACLE not available
ORA-27123: unable to attach to shared memory segment
HPUX-ia64 Error: 22: Invalid argument
Additional information: 1
Additional information: 884748
EXP-00005: all allowable logon attempts failed
EXP-00000: Export terminated unsuccessfully
hunter@HP:/home/hunter #ps -ef | grep ora_
  oracle 19161     1  0 09:50:17 ?         0:00 ora_d000_yxyup
  oracle 19169     1  0 09:50:22 ?         0:07 ora_arc1_yxyup
  oracle 19133     1  0 09:50:16 ?         0:03 ora_pmon_yxyup
  oracle 19135     1  0 09:50:16 ?         0:00 ora_psp0_yxyup
  oracle 19149     1  0 09:50:17 ?         0:08 ora_ckpt_yxyup
  oracle 19173     1  0 09:50:23 ?         0:00 ora_qmnc_yxyup
  hunter 27128 26727  0 16:05:31 pts/1     0:00 grep ora_
  oracle 19159     1  0 09:50:17 ?         0:10 ora_mmnl_yxyup
  oracle 19157     1  0 09:50:17 ?         0:01 ora_mmon_yxyup
  oracle 19185     1  0 09:50:33 ?         0:00 ora_q001_yxyup
  oracle 19183     1  0 09:50:33 ?         0:00 ora_q000_yxyup
  oracle 19167     1  0 09:50:22 ?         0:07 ora_arc0_yxyup
  oracle 19139     1  0 09:50:16 ?         0:01 ora_dbw0_yxyup
  oracle 19137     1  0 09:50:16 ?         0:07 ora_mman_yxyup
  oracle 19145     1  0 09:50:16 ?         0:00 ora_dbw3_yxyup
  oracle 19155     1  0 09:50:17 ?         0:11 ora_cjq0_yxyup
  oracle 19143     1  0 09:50:16 ?         0:40 ora_dbw2_yxyup
  oracle 19153     1  0 09:50:17 ?         0:00 ora_reco_yxyup
  oracle 19141     1  0 09:50:16 ?         0:00 ora_dbw1_yxyup
  oracle 19163     1  0 09:50:17 ?         0:00 ora_s000_yxyup
  oracle 19151     1  0 09:50:17 ?         0:01 ora_smon_yxyup
  oracle 19147     1  0 09:50:17 ?         0:26 ora_lgwr_yxyup
 
 
hunter@HP:/home/hunter #sqlplus /nolog                                                                            

SQL*Plus: Release 10.2.0.3.0 - Production on Mon Oct 22 16:44:38 2007

Copyright (c) 1982, 2006, Oracle.  All Rights Reserved.

SQL> conn system/hperh
ERROR:
ORA-01034: ORACLE not available
ORA-27123: unable to attach to shared memory segment
HPUX-ia64 Error: 22: Invalid argument
Additional information: 1
Additional information: 884748

oracle@HP:/home/oracle #sqlplus system/yxyup

SQL*Plus: Release 10.2.0.3.0 - Production on Mon Oct 22 17:01:43 2007

Copyright (c) 1982, 2006, Oracle.  All Rights Reserved.

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - 64bit Production
With the Partitioning and Data Mining options

SQL>

检查ORACLE_SID,ORACLE_HOME,LD_LIBRARY_PATH等环境变量都是正确的。都和oracle用户一样。
为什么只有oracle用户可以，其他用户不能登录

解决方法

oracle@HP:/u01/oracle/admin/yxyup/bdump #cd /u01/oracle/product/10.2.0.3/bin
oracle@HP:/u01/oracle/product/10.2.0.3/bin #chmod +s oracle
oracle@HP:/u01/oracle/product/10.2.0.3/bin #ls -l oracle
-rwsr-s---   1 oracle     dba        262570632 Oct 15 12:39 oracle