What is Dnsmasq for DHCP?
Dnsmasq is an open-source, lightweight, DNS caching and forwarding server. It is designed to provide DNS resolution for small and home networks. Dnsmasq provides local DNS caching, forwarding, and recursive lookups, as well as DHCP, TFTP, and other related services. It also has support for DNS and DHCPv6, as well as various other features such as DNS-over-TLS and IPv6 privacy extensions. Dnsmasq is a versatile and highly configurable tool that is simple to use. DNSMasq_DHCP is a feature of DNSMasq that provides a combined server to serve both DNS (Domain Name System) and DHCP (Dynamic Host Configuration Protocol) requests. It is a fast and lightweight DHCP server with support for both IPv4 and IPv6, and can be used to serve IP addresses to hosts on a LAN. DNSMasq_DHCP also offers features such as DNS and DHCP performance tuning, DHCP address range management, and support for multiple DNS domains.
This article specifically deals with monitoring dhcp. For more information on Dnsmasq, check DNS monitoring.
Monitoring Dnsmasq for DHCP with Netdata
The prerequisites for monitoring Dnsmasq for DHCP with Netdata are to have Dnsmasq DHCP and Netdata installed on your system.
Netdata auto discovers hundreds of services, and for those it doesn’t turning on manual discovery is a one line configuration. For more information on configuring Netdata for DnsmasqDHCP monitoring please read the collector documentation.
You should now see the dnsmasq dhcp section on the Overview tab in Netdata Cloud already populated with charts about all the metrics you care about.
Netdata has a public demo space (no login required) where you can explore different monitoring use-cases and get a feel for Netdata.
What Dnsmasq DHCP metrics are important to monitor?
dhcp_ranges
- Number of DHCP ranges in the network.
- ipv4 - Number of DHCP ranges on IPV4.
- ipv6 - Number of DHCP ranges on IPV6
dhcp_hosts
- Number of DHCP hosts in the network.
- ipv4 - Number of DHCP hosts on IPV4.
- ipv6 - Number of DHCP hosts on IPV6
dhcp_range_utilization
- Utilisation of IP addresses in a DHCP range.
- used - % of IP addresses utilised within the DHCP range.
This metric has a built-in alert. See below to learn more.
template: dnsmasq_dhcp_dhcp_range_utilization
on: dnsmasq_dhcp.dhcp_range_utilization
class: Utilization
type: DHCP
component: Dnsmasq
every: 10s
units: %
calc: $used
warn: $this > ( ($status >= $WARNING ) ? ( 80 ) : ( 90 ) )
crit: $this > ( ($status == $CRITICAL) ? ( 90 ) : ( 95 ) )
delay: down 5m
info: DHCP range utilization
to: sysadmin
dhcp_range_allocated_leases
- Number of allocated DHCP leases.
- leases - Number of allocated leases
