When you enable auditd logging on a Linux system, the generation of logs can be overwhelming. Some customer may want to disable an auditd entries related a specific command/SYSCALL. For example, below entries are being logged by auditd ( /var/log/messages )
type=CWD msg=audit(1464664627.639:1858714): cwd="/u01/app/oracle/emagent/12.1.0.3/agent_inst/sysman/emd" type=PATH msg=audit(1464664627.639:1858714): item=0 name="/u01/app/oracle/emagent/12.1.0.3/agent_inst/sysman/emd/upload/upload/stream0/" inode=17910851 dev=fc:03 mode=040740 ouid=1000 ogid=1001 rdev=00:00 type=PATH msg=audit(1464664627.639:1858714): item=1 name="/u01/app/oracle/emagent/12.1.0.3/agent_inst/sysman/emd/upload/upload/stream0/D_P4_S0_I174383.xml" inode=17913267 dev=fc:03 mode=0100640 ouid=1000 ogid=1001 rdev=00:00 type=SYSCALL msg=audit(1464664627.639:1858715): arch=c000003e syscall=87 per=400000 success=yes exit=0 a0=7f8b5c002180 a1=180 a2=7f8b5c002180 a3=7f8e9e1e3278 items=2 ppid=31951 pid=34940 auid=1075 uid=1000 gid=1001 euid=1000 suid=1000 fsuid=1000 egid=1001 sgid=1001 fsgid=1001 tty=(none) ses=17377 comm="java" exe="/u01/app/oracle/emagent/12.1.0.3/core/12.1.0.5.0/jdk/bin/java" key="delete" Customer would like to disable them as they are not necessary to be logged-in.
Disabling specific auditd logging entries
1. Easiest way to do is to simply disable path from Logging for example:
-W never,exclude -F path=/u01/app/oracle/emagent/12.1.0.3/ -k exclude
Above will exclude path /u01/app/oracle/emagent/12.1.0.3/ from being logged by auditd
2. Or simply disable separate rules by following below examples:
-W never,exclude -F exe=/u01/app/oracle/emagent/12.1.0.3/core/12.1.0.5.0/jdk/bin/java -k exclude -W never,exclude -F cwd=/u01/app/oracle/emagent/12.1.0.3/agent_inst/sysman/emd -k exclude -W never,exclude -F inode=17910851 -k exclude -W never,exclude -F inode=17913267 -k exclude
Above entries examples uses option like inode/exe/cwd
3. File which needs to be edited to add all above rules is located in- /etc/audit/audit.rules. Make sure you also comment in audit.rules below entry:
# Make the configuration immutable -- reboot is required to change audit rules #-e 2
4. Reboot will be required if “-e 2” was enabled. In normal cases simply restart auditd service:
# service auditd restart
For more information and examples of auditd rule, check the man page of auditctl.
# man auditctl
How to exclude specific users, groups, or services with Auditd to audit syscalls
How to exclude a file/directory from auditd rules