Key vfs.fs.discovery and mount bind

[dramon]

I am running Zabbix 2.0.5 on CentOS 5 machine with mounts:

/dev/md1 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/md0 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
/dev/md2 on /mnt/data type ext3 (rw,acl)
/dev/md3 on /mnt/db type ext3 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
/mnt/data/home on /home type none (rw,bind)
/mnt/data/mysql on /var/lib/mysql type none (rw,bind)
/mnt/data/www on /var/www type none (rw,bind)

when I try to list values for vfs.fs.discovery, I get:

{
"data":[
{
"{#FSNAME}":"\/",
"{#FSTYPE}":"rootfs"},
{
"{#FSNAME}":"\/",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/dev",
"{#FSTYPE}":"tmpfs"},
{
"{#FSNAME}":"\/proc",
"{#FSTYPE}":"proc"},
{
"{#FSNAME}":"\/sys",
"{#FSTYPE}":"sysfs"},
{
"{#FSNAME}":"\/selinux",
"{#FSTYPE}":"selinuxfs"},
{
"{#FSNAME}":"\/proc\/bus\/usb",
"{#FSTYPE}":"usbfs"},
{
"{#FSNAME}":"\/dev\/pts",
"{#FSTYPE}":"devpts"},
{
"{#FSNAME}":"\/boot",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/dev\/shm",
"{#FSTYPE}":"tmpfs"},
{
"{#FSNAME}":"\/mnt\/data",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/mnt\/db",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/proc\/sys\/fs\/binfmt_misc",
"{#FSTYPE}":"binfmt_misc"},
{
"{#FSNAME}":"\/misc",
"{#FSTYPE}":"autofs"},
{
"{#FSNAME}":"\/home",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/var\/lib\/mysql",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/var\/www",
"{#FSTYPE}":"ext3"},
{
"{#FSNAME}":"\/var\/named\/chroot\/proc",
"{#FSTYPE}":"proc"},
{
"{#FSNAME}":"\/var\/named\/chroot\/var\/run\/dbus",
"{#FSTYPE}":"ext3"}]}

And this is wrong becouse mount points mounted with "bind" option and with file system "none" are detected with "ext3" file system.

[just4fun]

Hi dramon,

this is "normal behaviour" as Zabbix utilizes /proc/mounts to find out which filesystems
have been mounted...

I'm not sure if there's another (easy) way to find only the "real" filesystems, maybe /etc/mtab
would be a better option?

[dramon]

OK.
The most easy way, how to solve this, will be to kick "vfs.fs.discovery" out and write my own bash script to send JSON list of filesystems using zabbix_send.
But I am not sure how many people really want to watch binded filesystems

[just4fun]

Hi dramon,

I've already fixed this by replacing the key "vfs.fs.discovery" with a self-written "vfs.fs.realdiscovery" (that I've added to each agent's UserParameter) and this "realdiscovery" only sends back "real" filesystems.

[spidernik84]

Hi dramon,

I've already fixed this by replacing the key "vfs.fs.discovery" with a self-written "vfs.fs.realdiscovery" (that I've added to each agent's UserParameter) and this "realdiscovery" only sends back "real" filesystems.

Hi just4fun, any chance you have that script still around?
I have the same need.

Thanks

[just4fun]

Hi spidernik,

it's not a script but a short C-programm:

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <mntent.h>

#include "cJSON.h"

int main (int argc, char **argv) {

        struct mntent   *m;
        FILE            *f;
        cJSON           *root, *data, *fsa, *fs;

        root = cJSON_CreateObject();

        cJSON_AddItemToObject(root, "data", fsa=cJSON_CreateArray());

        if (NULL != (f = setmntent("/etc/mtab", "r"))) {
                while (NULL != (m = getmntent(f))) {
                        cJSON_AddItemToArray(fsa, fs=cJSON_CreateObject());

                        cJSON_AddStringToObject(fs, "{#FSNAME}", m->mnt_dir);
                        cJSON_AddStringToObject(fs, "{#FSTYPE}", m->mnt_type);
                }

                endmntent(f);
        }

        printf ("%s\n", cJSON_Print(root));
}

Just look for the cJSON library from Dave Gamble (I don't remember where I
picked it up) and compile it. Works here for me for any RHEL-based system.