When the Oracle software is installed, the/dev/null0 file is created.
Reference text:
File/dev/null0 is Created after installation of Oracle software (Doc ID 1322550.1)
Suitable for:
Oracle database-enterprise edition-version 10.2.0.1 and later
Information in this document applies to any platform.
Symptoms:
For security reasons, only licensed files can appear in/dev.
1. On Hp-ia
[celchp4]/refresh/home> ls-al/dev/| grep null
Crw-rw-rw-1 Bin Bin 3 0x000002 may 07:30 null
-rw-r--r--1 root sys 0 Jul 1 null0
[celchp4]/refresh/home> Ll/dev/null
Crw-rw-rw-1 Bin Bin 3 0x000002 may 07:53/dev/null
[celchp4]/refresh/home> ll/dev/null0
-rw-r--r--1 root sys 0 Jul 1 2010/dev/null0
[celchp4]/refresh/home>
2. On IBM AIX
[celcaix4]/home/bugmnt> ls-al/dev/| grep null
Crw-rw-rw-1 root System 2, 2 May 07:58 null
-rw-r--r--1 root system 0 APR null0
CRW-------1 root System 7, 2 Jul sysdumpnull
[celcaix4]/home/bugmnt> Ll/dev/null
Crw-rw-rw-1 root System 2, 2 May 07:58/dev/null
[celcaix4]/home/bugmnt> ll/dev/null0
-rw-r--r--1 root system 0 APR 2010/dev/null0
[celcaix4]/home/bugmnt>
3. On Oracle Solaris
[celcsol4]/home/bugmnt> ls-al/dev/| grep null
lrwxrwxrwx 1 root root 9 Sep dtremote-/dev/null
lrwxrwxrwx 1 root other (null). /devices/pseudo/[email Protected]:null
-rw-r--r--1 root Other 0 null0
[celcsol4]/home/bugmnt>
4. On Linux
[Email protected]:/dev> ls-al/dev/| grep null
Crw-rw-rw-1 root root 1, 3 2009-02-24 03:06 null
lrwxrwxrwx 1 root root 4 2011-04-06 15:16 XOR, NULL
[Email protected]:/dev>
Change:
Oracle Software is installed
Reason:
Running root.sh will generate '/dev/null0 '.
[pst4:/]# ls/dev/null*
/dev/null
[pst4:/]#/db01/oracle/product/10.2/db_2/root.sh
Running Oracle10 root.sh Script ...
The following environment variables is set as:
Oracle_owner= Oracle
Oracle_home=/db01/oracle/product/10.2/db_2
Enter the full pathname of the local bin directory: [/usr/local/bin]:
The file "Dbhome" already exists in/usr/local/bin. Overwrite it? (y/n) [N]:
The file "Oraenv" already exists in/usr/local/bin. Overwrite it? (y/n) [N]:
The file "Coraenv" already exists in/usr/local/bin. Overwrite it? (y/n) [N]:
Entries'll be added to The/var/opt/oracle/oratab file as needed by
Database Configuration Assistant When a database is created
Finished running generic part of root.sh script.
Now product-specific root actions would be performed.
[pst4:/]# ls/dev/null*
/dev/null/dev/null0
[pst4:/]#
A. From root.sh script
#
# If LOG is not set and then send output to/dev/null
#
if ["x${log}" = "x"-O "${log}" = ""];then
Log=/dev/null
Else
$CP $LOG ${log}0 2>/dev/null
$ECHO "" > $LOG
Fi
B. From Truss output
91502 27646:execve ("/USR/BIN/CP", 0x0003b95c, 0x0003b978) argc = 3
91503 27646:ARGV:/usr/bin/cp/dev/null/dev/null0
91504 27646:envp:home=/Lang=posix
91505 27646:ld_library_path=:/usr/openwin/lib:/usr/x11r6/lib Logname=root
91506 27646:mail=/var/mail//root oldpwd=/
91507 27646:path=/usr/sbin:/usr/bin:/usr/openwin/bin:/usr/x11r6/bin:.
91508 27646:ps1=[pst4: $PWD]# pwd=/db01/oracle/product/10.2/db_2
91509 27646:shell=/bin/bash shlvl=1 ssh_client=10.179.117.70 2617 22
91510 27646:ssh_connection=10.179.117.70 2617 10.179.112.34 22
91511 27646:SSH_TTY=/DEV/PTS/2 term=xterm Tz=rok user=root
91512 27646: _=/usr/bin/truss
91513 27646:resolvepath ("/usr/lib/ld.so.1", "/lib/ld.so.1", 1023) = 12
...
91577 27646:munmap (0xff260000, 32768) = 0
91578 27646:pathconf ("/dev/null", 20) = 1
91579 27646:acl ("/dev/null", getaclcnt, 0, 0x00000000) = 4
91580 27646:stat64 ("/dev/null", 0xffbfeda0) = 0
91581 27646:acl ("/dev/null", Getacl, 4, 0X000276C8) = 4
91582 27646:stat64 ("/dev/null0", 0x00026630) = 0
91583 27646:stat64 ("/dev/null0", 0x00026630) = 0
91584 27646:open64 ("/dev/null", o_rdonly) = 3
91585 27646:creat64 ("/dev/null0", 0666) = 4
91586 27646:stat64 ("/dev/null0", 0x00026630) = 0
91587 27646:fstat64 (3, 0X000266C8) = 0
91588 27646:read (3, 0xffbf6f00, 32768) = 0
Solution:
Ignore this behavior and delete the '/dev/null0 ' file as long as no process is using this file (use lsof or fuser or any other appropriate tool to check whether the null0 is being used by the process)
"Translated from MoS article" when the Oracle software is installed, the/dev/null0 file is created.
