How do I check disk usage on my Linux server?

View a step-by-step screencast of this process:

Log into the RHEL server as root via PuTTY, or shell out from Eterm.

The “df” command is used to determine overall filesystem usage. The “vgs” command will show you any space available in the volume group that has not yet been allocated to a specific filesystem.

To see the total size of each filesystem:

df -h

The standard Eclipse filesystems are located under /u2. Add the “Used” column for each of these filesystems, plus any non-standard Eclipse filesystems that you may have (/train, /backup, etc.).

[root@firestorm ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/rootvg-root
                       20G   18G  1.1G  95% /
/dev/mapper/datavg-u2
                      3.9G  2.1G  1.6G  57% /u2
/dev/mapper/datavg-uvtmp
                      3.9G  137M  3.6G   4% /u2/uvtmp
/dev/mapper/rootvg-esupport
                      5.9G  3.4G  2.3G  60% /esupport
/dev/sda1              99M   26M   69M  28% /boot
tmpfs                 3.9G     0  3.9G   0% /dev/shm
/dev/mapper/datavg-eclipse
                       26G   17G  7.6G  69% /u2/eclipse
/dev/mapper/datavg-ereports
                      992M   34M  908M   4% /u2/eclipse/ereports
/dev/mapper/datavg-lvol0
                      3.9G  2.1G  1.6G  57% /snap/u2
/dev/mapper/datavg-lvol4
                      3.9G  137M  3.6G   4% /snap/u2/uvtmp
/dev/mapper/datavg-lvol6
                       26G   17G  7.6G  69% /snap/u2/eclipse

If you would like to identify which files or subdirectories are using the most space in a particular filesystem or directory, you may use the “du” command. For example, to list the disk usage of top files and directories under /u2/eclipse in megabytes:

[root@firestorm ~]# cd /u2/eclipse
[root@firestorm eclipse]# du -sm * | sort -rn | head
3780    modules-linux
2856    modules
1568    ZIP4
859     jsdata
740     PHANTOM.LOG
740     modules-test
450     8.6.9.00.16-aix.zip
447     8.6.9.00.99-aix.zip
446     8.6.9.00.11-aix.zip
428     8.6.9.00.13-aix.zip

If you would like to see how much space is available for allocation within the volume group:

vgs

For more detail on this process, see: How do I expand a Linux file system?

Alternatively, if you prefer a graphical tool, you may log into the server’s GUI, and use the Disk Usage Analyzer tool:

  • Log into the server’s GUI (see also How do I access the GUI of my Linux server?)
  • Applications -> System Tools -> Disk Usage Analyzer
  • Click the Filesystem button to begin storage analysis of your entire system
  • Use the controls to drill down into each subdirectory for a graphical picture of storage utilization

How do I check the status of my ABS backup on my Linux server?

All successful backups of an Eclipse database server, regardless of the backup software being used, require the successful completion of both of the following two, separate processes:

  • Prepare: the snapshot process that prepares a point-in-time, frozen “picture” of the database and application files. For an overview of this process, see How do filesystem snapshots work on Linux?
  • Capture: the backup software process(es) that take this snapshot data and transfer to any sort of archival media (disk, tape, online vault, etc.)

For ABS customers, a successful backup requires a successful database snapshot and a successful CrashPlan backup running to completion between snapshot intervals. This article will review how to check the status of both processes.

Part 1: Snapshot Verification

First, we must verify that the snapshot process has completed successfully.

Log into the server as root via command line or GUI.

Open the /tmp/snapsave.log via your preferred text editor. For example, using less from the command line:

less /tmp/snapsave.log

Review the log for the following items:

  • Date/time the snapshot was created
  • Whether or not the snapshot operation was successful, or if any warnings/errors were generated

Because each snapshot volume is of a fixed size, it’s possible for snapshots to run out of room. You may check the current snapshot status using the lvs command and noting the values in the “Snap%” column:

[root@firestorm ~]# lvs
  LV       VG     Attr   LSize  Origin   Snap%  Move Log Copy%  Convert
  eclipse  datavg owi-ao 50.00G                                        
  ereports datavg owi-ao  1.00G                                        
  lvol0    datavg swi-ao  1.00G u2         6.01                        
  lvol1    datavg swi-ao  1.00G eclipse    8.52                        
  lvol2    datavg swi-ao  1.00G ereports   0.00                        
  u2       datavg owi-ao  2.00G                                        
  uvtmp    datavg -wi-ao  4.00G                                        
  backup   rootvg -wi-ao 50.00G                                        
  esupport rootvg -wi-ao 40.00G                                        
  root     rootvg -wi-ao 40.00G                                        
  swap     rootvg -wi-ao  4.00G

If any of these values are 100%, the snapshot became invalid at some point by holding too many changes. Since we’re attempting to verify the backup was successful, we’ll want to note the date/time that the snapshot became invalid, to verify that the CrashPlan process completed prior to the snapshot becoming invalid. The /var/log/messages file contains timestamped entries for all snapshot events, so the following command will show you any relevant snapshot-related messages, including when a snapshot is no longer being monitored:

grep snapshot /var/log/messages

As an alternative to manually checking the snapsave.log file on a daily basis, you may opt to configure your system to automatically email this log to your regular address using the instructions found in How do I forward root’s mail to another address?

Part 2: CrashPlan Verification

Next, we must verify that CrashPlan was able to archive all of the snapshot data successfully between the time the previous snapshot completed and the next one was started (typically 24 hours).

If you prefer using the command line, you may verify the last few most recent backups using the following command:

egrep "Starting|Completed" /usr/local/crashplan/log/history.log.0 | tail

There are a few things to note in this output:

  • The backup process should have started after the snapshot was created
  • The backup process should have completed before the next snapshot was scheduled to be created, or before the snapshot filled to capacity

If you prefer to use the GUI, this same historical information is visible from the CrashPlan Desktop interface.

View a step-by-step screencast of this process:

  • Log into the server’s GUI via VNC, the DRAC, or the local console
  • Double-click the CrashPlanDesktop icon to launch the CrashPlan client interface. If there is no shortcut, follow these instructions to create one.
  • The CrashPlan GUI opens to the “Backup” dashboard, and the current status of each separate backup job is displayed
  • For additional information, select the History tab and scroll through the detailed history.

How do I set the IP address on my Linux server?

To set the IP address via the GUI:

To set the IP address via the command line:

Set the default gateway:

vim /etc/sysconfig/network

Change the GATEWAY line, save and quit

Set the IP address and network mask:

vim /etc/sysconfig/network-scripts/ifcfg-eth0

Change the IPADDR, GATEWAY and NETMASK lines, save and quit

 

DRAC Network Configuration

This article will show you how to configure the IP address on your Dell Remote Access Controller (DRAC).

Configure the DRAC IP address using the front panel (12th generation servers)

If you have a 12th generation server (i.e. R720, R620, R320, T620, T320) with an LCD front-panel display, you can configure the IP address directly from the front panel, somewhat like configuring an IP address on a print server.

The IP address can be configured at any time, and the server does not need to be rebooted.

The Home screen displays user-configurable information about the system. This screen is displayed during normal system operation when there are no status messages or errors. When the system is in standby mode, the LCD backlight turns off after five minutes of inactivity if there are no error messages. Press one of the three navigation buttons (Select,
Left, or Right) to view the Home screen.

To navigate to the Home screen from another menu, continue to select the up arrow until the Home icon is displayed, and then select the Home icon. From the Home screen, press the Select button to enter the main menu.

From the home screen, use the select and arrow buttons to enter the Setup menu, then select iDRAC, and then select Static IP.

At the next screen, use the arrows and select buttons to set the IP address.

After the IP address is configured, follow the same procedure to set the subnet mask and default gateway.

Navigate back to the Home screen, and you will be able to access the DRAC via your web browser at the IP address you just configured within a couple minutes.

Configure the DRAC IP address from the BIOS

The IP address of the DRAC can be configured in the BIOS (aka configuration utility) using the instructions below. To view a step-by-step screencast of this process, click here.

Power on or restart your server.

After the Dell logo appears, you will see a message about the DRAC configuration utility. When this appears, press <Ctrl><E> as prompted. If you miss the prompt, restart the server and try again.

Once you are in the DRAC configuration utility, use the keyboard arrow keys to select LAN Parameters and then press <Enter> to display the NIC Selection menu.

Use the arrow keys to select the Dedicated mode, unless your server does not have the dedicated DRAC network port (a separate network port on the back of the server with a “wrench” symbol on it). If your server doesn’t have a dedicated DRAC network port, you may select the shared option.

Use the arrow keys to select LAN Parameters, and press <Enter>.

Using the up-arrow and down-arrow keys, select IP Address Source.

Using the right-arrow and left-arrow keys, select Static.

Selected Static, configure the Ethernet IP Address, Subnet Mask, and Default Gateway settings.

Press <Esc>, then <Esc> again to exit the menus, until prompted to select select Save Changes and Exit.

The server will reboot, and you will be able to access the DRAC via your web browser at the IP address you just configured within a couple minutes.

How do I monitor system performance using nmon?

nmon is a free console-based performance monitoring tool from IBM. It works on both AIX and RHEL.

If nmon is not already installed, you must first install it:

To use nmon:

View a step-by-step screencast of this process:
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  • Log into your server as root using a terminal emulator such as PuTTy (see also: How do I use PuTTy with my Eclipse server?)
  • (AIX only) Set the terminal emulation type to match the PuTTy console:
    export TERM=xterm
  • Run:
    nmon
  • Press the appropriate keys to launch or close various monitoring windows. Type “h” for help. Here are some common views:
    • “t”: display top processes
    • “t” then”u”: display top processes by CPU utilization and show command line arguments
    • “c”: display CPU utilization
    • “l”: display longer-term CPU utilization averages
    • “d”: display disk I/O graphs
    • “h”: display help

Resources: