title: FATAL: Module sg not found
body: <p>When I was installing uptime monitoring agent, I got the error messages:</p>
  
  <pre><code>Probing 'sg' devices
  FATAL: Module sg not found.
  </code></pre>
  
  <p>But lsmod shows the sg module is loaded:</p>
  
  <pre><code># cat /etc/redhat-release
  Red Hat Enterprise Linux Server release 6.1 (Santiago)
  # uname -r
  2.6.32-131.0.15.el6.x86_64
  
  # cat /proc/scsi/sg/version
  30534   3.5.34 [20061027]
  
  # find /lib/modules -name sg.ko
  /lib/modules/2.6.32-131.0.15.el6.x86_64/kernel/drivers/scsi/sg.ko
  
  # lsmod |grep sg
  sg                     30186  0
  
  # modprobe -lv|grep sg
  # 
  # cat /boot/config-`uname -r` | grep CONFIG_CHR_DEV_SG
  CONFIG_CHR_DEV_SG=m
  </code></pre>
  
  <p>Following is the device and file system information:</p>
  
  <pre><code># pvs
    PV         VG             Fmt  Attr PSize   PFree
    /dev/sda2  vg0            lvm2 a-   499.51g 113.51g
  
  # df -hF ext4
  Filesystem            Size  Used Avail Use% Mounted on
  /dev/mapper/vg0-lv_root
                         99G  7.9G   86G   9% /
  /dev/sda1             485M   36M  425M   8% /boot
  /dev/mapper/vg0-lv_opt
                         99G  189M   94G   1% /opt
  /dev/mapper/vg0-lv_var
                        148G  114G   27G  82% /var
  
  
  # grep kernel /var/log/messages | grep sg
  Jul 21 03:25:04 server810 kernel: imklog 4.6.2, log source = /proc/kmsg started.
  
  # ls /dev/sg*
  /dev/sg0  /dev/sg1
  
  # ls -l /dev/sg*
  crw-rw---- 1 root cdrom 21, 0 Jul 14 11:10 /dev/sg0
  crw-rw---- 1 root disk  21, 1 Jul 14 11:10 /dev/sg1
  </code></pre>
  
  <p>The server is a VMWare guest.</p>
  
  <p>Any help will be highly appreciated.</p>
  
  <p>Thanks in advance,</p>
  
  <p>Alex</p>