Neutron DHCP Agent Fails to Start dnsmasq: "dnsmasq: bad command line options

Problem

  • Instances spawned on networks that rely on the DHCP agent(s) which are affected are failing to obtain a DHCP lease.

  • The pf9-neutron-dhcp-agent service is failing to spawn the dnsmasq process with the following printed in its log at /var/log/pf9/pf9-neutron-dhcp-agent.log.

ERROR neutron.agent.linux.utils [-] Exit code: 1; Stdin: ; Stdout: ; Stderr:dnsmasq: bad command line options: try --helpERROR neutron.agent.linux.dhcp [-] Failed to start DHCP process for network [NETWORK_ID]: WaitTimeout: Timed out after 60 seconds

Environment

  • Platform9 Managed OpenStack - v3.11 and Higher

Cause

The dnsmasq package installed on the affected host(s) is incompatible with the version required by the neutron-dhcp-agent.

Resolution

  1. Install dnsmasq 2.76 or higher.

# yum update -y dnsmasq


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Neutron DHCP Agent Fails to Start dnsmasq: "dnsmasq: bad command line optionsProblemEnvironmentCauseResolution