DHCPv4, Exhausted Lease Pool

Contents

1Introduction
1.1Alarm Description
1.2Prerequisites

2
Procedure
2.1Adding More Leases
2.2Changing Lease Pool Configuration

1   Introduction

This instruction concerns alarm handling.

1.1   Alarm Description

This alarm is issued when no suitable lease is found in the lease pool of DHCPv4 server or vendor ID is not allowed.

The possible alarm causes and the corresponding fault reasons, fault locations, and impacts are described in Table 1.

Table 1    Alarm Causes

Alarm Cause

Description

Fault Reason

Fault Location

Impact

Solution

No lease in the lease pool of DHCPv4 server.

There is no more lease in the lease pool for DHCP client.

Lease exhausted.

DHCPv4 server

Certain DHCP client cannot get IP address.

See Section 2.1 Adding More Leases

Vendor ID is not allowed.

The vendor ID in DHCP request is not allowed or configured for the lease pool.

Configuration error.

DHCPv4 server

See Section 2.2 Changing Lease Pool Configuration

Note:  
An alarm can appear as a result of the maintenance activity.

The alarm attributes are listed and explained in Table 2.

Table 2    Alarm Attributes

Attribute Name

Attribute Value

Major Type

193

Minor Type

872455

Managed Object Class

IpworksDhcpv4

Source

ManagedElement=<Node Name>,SystemFunctions=1,Fm=1,FmAlarmModel=ipworksDHCPv4,FmAlarmType=ipworksDhcpv4ExhaustedLeasePool,HostName=<PL hostname>

Specific Problem

DHCPv4, Exhausted Lease Pool

Event Type

processingErrorAlarm(10)

Probable Cause

x733UnderlyingResourceUnavailable(356)

Additional Text

This alarm is raised when no suitable lease is found in DHCPv4 Server's Lease Pool or Vendor Id is not allowed, check it.;uuid:<Product_UUID>(1)

Perceived Severity

Critical

(1)  <Product_UUID> is the universally unique identifier (UUID) of machine that generates the alarm. The value can be fetched from /sys/devices/virtual/dmi/id/product_uuid on the PL node.


1.2   Prerequisites

This section provides information on the documents, tools, and conditions that apply to the procedure.

1.2.1   Documents

Before starting this procedure, ensure that you have read the following documents:

1.2.2   Tools

No tools are required.

1.2.3   Conditions

No conditions.

2   Procedure

This section describes the procedure to clear this alarm.

2.1   Adding More Leases

Do the following:

  1. Add more leases for DHCPv4 server. For example:

    # ipwcli

    #IPWorks> modify pool pool0 -set addressrange=10.170.15.101-140

  2. Update DHCPv4 server.

    # IPWorks> update dhcpv4server

  3. Restart DHCPv4 server. For example:

    # ipw-ctr restart dhcp <PL hostname>

  4. Clear the alarm manually. For example:
    1. Check “specificProblem” in alarm list, and get the alarm id:

      # ipw-alarm --cmd list

      FmAlarm=167
   activeSeverity=CRITICAL <read-only>
   additionalText="This alarm is raised when no suitable lease is found in DHCPv4 Server's Lease Pool or Vendor Id is not allowed, check it." <read-only>
   eventType=PROCESSINGERRORALARM <read-only>
   fmAlarmId="167"
   lastEventTime="2017-12-11T10:08:57.280+01:00" <read-only>
   majorType=193 <read-only>
   minorType=872455 <read-only>
   originalAdditionalText="This alarm is raised when no suitable lease is found in DHCPv4 Server's Lease Pool or Vendor Id is not allowed, check it." <read-only>
   originalEventTime="2017-12-11T10:08:57.280+01:00" <read-only>
   originalSeverity=CRITICAL <read-only>
   probableCause=356 <read-only>
   sequenceNumber=343 <read-only>
   source="ManagedElement=ipworks_cba,SystemFunctions=1,Fm=1,FmAlarmModel=ipworksDHCPv4,FmAlarmType=ipworksDhcpv4ExhaustedLeasePool,HostName=PL-3,IpworksDhcpv4" <read-only>
   specificProblem="DHCPv4, Exhausted Lease Pool" <read-only>
   additionalInfo[@1] <read-only>
      name="" <read-only>
      value="73599686-825A-438E-B8FE-3F095A881027" <read-only>

    2. Clear the alarm by alarm id:

      # ipw-alarm --cmd clear –id <Alarm ID>.

      Note:  
      Get the usage of command "ipw-alarm" by entering the command without any arguments.

  5. If the alarm remains, consult the next level of maintenance support. Further actions are outside the scope of this instruction.

2.2   Changing Lease Pool Configuration

Do the following:

  1. Change the configuration of Lease Pool for DHCPv4 server. For example:

    #ipwcli

    #IPWorks> modify pool pool0 -set AllowedClient=all;DeniedClient=unknown

  2. Update DHCPv4 server.

    #IPWorks> update dhcpv4server

  3. Restart DHCPv4 server. For example:

    # ipw-ctr restart dhcp <PL hostname>

  4. Clear the alarm manually. For example:
    1. Check “specificProblem” in alarm list, and get the alarm id:

      # ipw-alarm --cmd list

    2. Clear the alarm by alarm id:

      # ipw-alarm --cmd clear –id <Alarm ID>.

      Note:  
      Get the usage of command "ipw-alarm" by entering the command without any arguments.

  5. Confirm that the alarm has ceased. If the alarm remains, consult the next level of maintenance support. Further actions are outside the scope of this instruction.


    DHCPv4, Exhausted Lease Pool