On AIX, there is no stat command and therefore the getOwnerIdOf check fails.
# ls -al /tmp/.com_ibm_tools_attach/
total 24
drwxrwxrwt 3 root system 4096 Jul 02 06:21 .
drwxrwxrwt 45 bin bin 8192 Jul 02 06:20 ..
drwx--x--t 2 testuser staff 256 Jul 02 06:21 8061236
-rw-rw-rw- 1 root system 0 Jan 16 2020 _attachlock
-rw-rw-rw- 1 root system 0 Nov 21 2023 _controller
-rw-rw-rw- 1 root system 0 Jan 16 2020 _master
-rwxrwxrwx 1 root system 0 Jan 16 2020 _notifier
The istat command does not offer an output to only get the Owner PID, therefore we have to use a Pattern matcher to get it.
# istat /tmp/.com_ibm_tools_attach/8061236
Inode 45058 on device 10/7 Directory
Protection: rwx--x--x Sticky
Owner: 205(testuser) Group: 1(staff)
Link count: 2 Length 256 bytes
Last updated: Tue Jul 2 06:21:53 EDT 2024
Last modified: Tue Jul 2 06:21:53 EDT 2024
Last accessed: Tue Jul 2 06:21:52 EDT 2024
In our use case this is only relevant for J9 based JVMs running below Java 10 as they require the same user as the target JVM.
With a root user otherwise, the OwnerId is not checked and we are fine.
The Exception that we see with the current code:
2024-06-13T04:24:37.828-05:00 | ERROR | instana-executor-thread-30-7 | ExternalAttach | com.instana.agent - 1.1.723 | java.lang.IllegalStateException: Unable to execute stat command
at net.bytebuddy.agent.VirtualMachine$ForOpenJ9$Dispatcher$ForJnaPosixEnvironment.getOwnerIdOf(VirtualMachine.java:2182)
at net.bytebuddy.agent.VirtualMachine$ForOpenJ9.attach(VirtualMachine.java:1695)
at net.bytebuddy.agent.VirtualMachine$ForOpenJ9.attach(VirtualMachine.java:1663)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:90)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:55)
at java.lang.reflect.Method.invoke(Method.java:508)
at com.instana.agent.loader.AgentLoaderAttach.attach(AgentLoaderAttach.java:398)
at com.instana.agent.loader.AgentLoaderAttach.run(AgentLoaderAttach.java:150)
at com.instana.agent.loader.AgentLoaderAttach.parseArgsAndRun(AgentLoaderAttach.java:100)
at com.instana.agent.loader.AgentLoaderAttach.main(AgentLoaderAttach.java:83)
Caused by: java.io.IOException: Cannot run program "stat": error=2, A file or directory in the path name does not exist.
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1059)
at java.lang.Runtime.exec(Runtime.java:631)
at java.lang.Runtime.exec(Runtime.java:496)
at net.bytebuddy.agent.VirtualMachine$ForOpenJ9$Dispatcher$ForJnaPosixEnvironment.getOwnerIdOf(VirtualMachine.java:2153)
... 10 more
Caused by: java.io.IOException: error=2, A file or directory in the path name does not exist.
at java.lang.UNIXProcess.forkAndExec(Native Method)
at java.lang.UNIXProcess.<init>(UNIXProcess.java:291)
at java.lang.ProcessImpl.start(ProcessImpl.java:167)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1040)
... 13 more
On AIX, there is no
statcommand and therefore thegetOwnerIdOfcheck fails.The
istatcommand does not offer an output to only get the Owner PID, therefore we have to use a Pattern matcher to get it.In our use case this is only relevant for J9 based JVMs running below Java 10 as they require the same user as the target JVM.
With a root user otherwise, the OwnerId is not checked and we are fine.
The Exception that we see with the current code: