KMP http://www.net24.co.nz/kb/category/8 en-us KnowlageBase RSS Generator How to rebuild Geom mirror in FreeBSD http://www.net24.co.nz/kb/article/AA-00102 This article discusses how to rebuild a Geom mirror after a faulty drive has been replaced.

Root Privileges Required

All commands listed in this article need to be executed with root privileges.

Step 1 - Identify Replaced Drive

  1. Log in to your server and as root run the following command:
    # gmirror list
  2. This will produce output similar to the following
    Geom name: gm0
    State: DEGRADED
    Components: 2
    Balance: round-robin
    Slice: 4096
    Flags: NONE
    GenID: 0
    SyncID: 3
    ID: 3594034660
    Providers:
    1. Name: mirror/gm0
       Mediasize: 159999999488 (149G)
       Sectorsize: 512
       Mode: r2w2e5
    Consumers:
    1. Name: ad4
       Mediasize: 160000000000 (149G)
       Sectorsize: 512
       Mode: r1w1e1
       State: ACTIVE
       Priority: 0
       Flags: DIRTY
       GenID: 0
       SyncID: 3
       ID: 4064102945

    In this example we can see the status of the mirror is degraded and the only active drive is 'ad4'.

  3. To find out which drives are available and the corresponding device name run the atacontrol list command.
    # atacontrol list

    This will produce a list of drives with device names which are connected to your server.

    ATA channel 2:
        Master:  ad4 <WDC WD1602ABKS-18N8A0/02.03B04> SATA revision 2.x
        Slave:       no device present
    ATA channel 3:
        Master:  ad6 <WDC WD2502ABYS-02B7A0/02.03B03> SATA revision 2.x
        Slave:       no device present

    From this we can see that device '*ad6*' is the device name of the new drive we can use to rebuild the mirror. You should already be aware of the device name from alerts generated by your server when the drive failed; the replacement drive will show up with the same device name.

Step 2 - Rebuild Mirror

  1. Now that we have verified device name of the new drive we can easily rebuild the array using the following commands:
    # gmirror forget gm0
    # gmirror insert gm0 <device>

    Where <device> is the device name of the new drive we determined above. In the example above <device> would be 'ad6'.

  2. To verify the drive has been added to the mirror and the mirror is being rebuild run the '*gmirror list'* command.
    # gmirror list
    Geom name: gm0
    State: DEGRADED
    Components: 2
    Balance: round-robin
    Slice: 4096
    Flags: NONE
    GenID: 0
    SyncID: 3
    ID: 3594034660
    Providers:
    1. Name: mirror/gm0
       Mediasize: 159999999488 (149G)
       Sectorsize: 512
       Mode: r3w2e5
    Consumers:
    1. Name: ad4
       Mediasize: 160000000000 (149G)
       Sectorsize: 512
       Mode: r1w1e1
       State: ACTIVE
       Priority: 0
       Flags: NONE
       GenID: 0
       SyncID: 3
       ID: 4064102945
    2. Name: ad6
       Mediasize: 251059544064 (234G)
       Sectorsize: 512
       Mode: r1w1e1
       State: SYNCHRONIZING
       Priority: 0
       Flags: DIRTY, SYNCHRONIZING
       GenID: 0
       SyncID: 3
       Synchronized: 3%
       ID: 2247886846

    We can see here the new drive has been added and the mirror is being rebuilt (3% complete). Rebuild times can take anywhere from 20 minutes to a few hours depending on the size of the drives and the amount of application I/O on your system.

    The first few lines show that overall state of the mirror, once the state changes from 'DEGRADED' to 'COMPLETE' the rebuild is complete.

]]> Fri, 30 Jul 2010 01:45:38 +1200 RSA remote console screen is blank http://www.net24.co.nz/kb/article/AA-00105 When using the IBM Remote Supervisor Adapter's Remote Console feature the screen is blank and no video is displayed.

Cause

The RSA Remote Console uses UDP to transfer screen information to the client. If you are behind a firewall these packets may be blocked.

Resolution

Open up access on your firewall to allow the required UDP packets to reach your client machine. The table below shows the ports and protocols used for remote console access.
ProtocolSource Address
Source Port
Destination Address
Destination Port
 UDP <RSA IP Address> 2000 <Client Computer Accessing RSA> > 1024

Random Destination Port Above 1024 Required

The RSA sends Remote Console UDP packets to a random port above 1024, therefore it is necessary to create a firewall rule to allow UDP packets from the RSA IP address to all UDP ports above 1024.

]]> Sat, 05 Jun 2010 23:40:57 +1200 Key repeating makes it difficult to use RSA remote console http://www.net24.co.nz/kb/article/AA-00104 Issue

When you use the Remote Supervisor Adapter's Remote Console, key presses are repeated multiple times on the server making it difficult or impossible to use.

Cause

This problem can occur if you are using the Remote Supervisor Adapter's Remote Console over a slow connection.

Resolution

Disable the key repeat function in the Operating System. For Windows follow the instructions below:

  1. Run '*Start > Programs > Accessories > Accessibility > Accessibility Wizard*'.
  2. Navigate your way through the wizard until you reach the page that contains the option '*I have difficulty using the keyboard or mouse*' and then check this option.
  3. On the BounceKeys page select '*Yes*'.
  4. The keystroke repeat rate of 0.50 seconds should be sufficient to resolve the issue.


]]> Sat, 05 Jun 2010 23:28:49 +1200 Java errors when using IBM RSA remote control features http://www.net24.co.nz/kb/article/AA-00103 Issue

When attempting to use the IBM Remote Control feature of the RSA you receive a Java error preventing you from logging in.

Resolution

This issue is due to a bug with the RSA that only affects customers with the latests versions of Java greater than 1.6.0_11. The resolution is to downgrade your Java version to 1.6.0_11 or lower


]]> Sat, 05 Jun 2010 23:24:08 +1200