snmp | A high-performance SNMP v3 client library in Go

1. Are you sure you are running php -m on the docker container and not your host?(quite common mistake)

2. In your symfony(fpm) docker container 127.0.0.1 and localhost resolve to the container itself, not your host machine which has the db exposed on port 3309. Try changing your DATABASE_URL to mysql://root:root@myApp-back-db:3306. Also, you can try setting url to host.docker.internal if you are on mac or windows.

3. Create a docker file for fpm and install mysql ext:

docker-composer:

You can use os modules for this.

I'm unfamiliar with SNMP4J, but this block of code may need to have the security level defined as authPriv or however SNMP4J refers to it:

Disclaimer I am not expert so take the following with a pinch of salt.

I cannot say for the library you are using but regarding the SNMP v3 flow:

In SNMPv3 exchanges, the USM is responsible for validation only on the SNMP authoritative engine side, the authoritative role depending of the kind of message.

• Agent authoritative for : GET / SET / TRAP
• Receiver authoritative for : INFORM

The RFC 3414 describes the reception of message in section 3.2 :

1. If the information about the user indicates that it does not support the securityLevel requested by the caller, then the usmStatsUnsupportedSecLevels counter is incremented and an error indication (unsupportedSecurityLevel) together with the OID and value of the incremented counter is returned to the calling module.

2. If the securityLevel specifies that the message is to be authenticated, then the message is authenticated according to the user’s authentication protocol. To do so a call is made to the authentication module that implements the user’s authentication protocol according to the abstract service primitive

So in the step 6, the securityLevel is the one from the message. This means the TRAP is accepted by the USM layer on the receiver side even if the authentication is not provided.

It is then the task of the user of the TRAP to decide if the message must be interpreted or not.

I don't know of a way to test a community without doing an SNMP operation. It's not necessary to walk. You can do a single GET to something common like .1.3.6.1.2.1.1.5.0 (SNMPv2-MIB::sysName) as a test.

There are two issues here:

1. Oracle Database is not supported on ARM processors, only Intel. See here: https://github.com/oracle/docker-images/issues/1814
2. Oracle Database Docker images are only supported with Oracle Linux 7 or Red Hat Enterprise Linux 7 as the host OS. See here: https://github.com/oracle/docker-images/tree/main/OracleDatabase/SingleInstance

Oracle Database ... is supported for Oracle Linux 7 and Red Hat Enterprise Linux (RHEL) 7. For more details please see My Oracle Support note: Oracle Support for Database Running on Docker (Doc ID 2216342.1)

The referenced My Oracle Support Doc ID goes on to say that the database binaries in their Docker image are built specifically for Oracle Linux hosts, and will also work on Red Hat. That's it.

Because Docker provides process level virtualization it still pulls kernel and other OS libraries from the underlying host OS. A Docker image built for Oracle Linux needs an Oracle Linux host; it doesn't bring the Oracle Linux OS with it. Only Oracle Linux or Red Hat Linux are supported for any Oracle database Linux installation, with or without Docker. Ubuntu, Mac OS, Debian, or any other *NIX flavor will not provide predictable reliable results, even if it is hacked into working or the processes appear to work normally.

The problem here is that jvmMemPoolMaxSize (OID .1.3.6.1.4.1.42.2.145.3.163.1.1.2.110.1.13) is defined in JVM-MANAGEMENT-MIB as type JvmUnsigned64TC, which seems kind of strange because Java specifically forbids the use of unsigned integer types.

The description for jvmMemPoolMaxSize implies that it's meant to represent the value returned by java.lang.management.MemoryPoolMXBean.getUsage().getMax(). The documentation for that method says "This method returns -1 if the maximum memory size is undefined."

The description of jvmMgmMIB addresses the issue with this explanation:

Where the Java programming language API uses long, or int, the MIB often uses the corresponding unsigned quantity - which is closer to the object semantics.

In those cases, it often happens that the -1 value that might be used by the API to indicate an unknown/unimplemented value cannot be used. Instead the MIB uses the value 0, which stricly speaking cannot be distinguished from a valid value. In many cases however, a running system will have non-zero values, so using 0 instead of -1 to indicate an unknown quantity does not lose any functionality.

I think it's safe to say this is one of the cases where a zero is not valid, so you should take it to mean that there is no defined maximum.

You must grant write privileges to actual dbPath (in your case /home/vojtam/disk/mongodb) but also to all parent folders.

Home directories like /home/vojtam are usually accessible only for the owner, that's why they are called "home directory". The permissions of any sub-folder does not matter.

By default MongoDB process runs by user mongod, and typically a service is provided to any user of a system. Thus you should prefer a common folder for example /var/lib/mongo as used in defaults.

According this line