Lease

Lease is a DHCP software suite consisting of DHCPv4 and DHCPv6 servers, relay agents, clients, and various utilities.

Install Lease 1.99.7 Documentation Support

Contents

What is Lease?

Lease is an enterprise-grade DHCP software distribution. It is maintained as a DHCP reference implementation by closely adhering to the DHCP standards. Lease includes the following programs:

  • dhcpd — DHCPv4 and DHCPv6 server
  • dhcrelay — DHCPv4 and DHCPv6 relay agent
  • dhclient — DHCPv4 and DHCPv6 client
  • omshell — provides an interactive way to connect to, query, and possibly change dhcpd's state via OMAPI

These programs implement various DHCP protocols and features. Lease programs and their config files are extensively documented in the Lease User Manual and manpages.

Why use Lease?

Here are some reasons for using Lease:

  • You want to automatically configure your client host using settings received via DHCP.
  • You have a large number of hosts and want to conveniently manage and auto-configure their network settings dynamically.
  • You want a well-documented DHCP product.

Lease features

The following are some of the features implemented by Lease.

DHCP server

  • dhcpd implements DHCPv4 and DHCPv6 server modes via -4/-6 commandline switches
  • Supports BOOTP clients with static host declarations or dynamic assignment
  • Lease durations and renewal behavior: default and maximum lease times, renewals, expirations
  • Maintains persistent lease state via a dhcpd.leases file with periodic compaction
  • On startup, replays lease database to restore in-memory state

Configuration & operation

  • dhcpd.conf configuration file supports subnet, pool, host, group, option declarations
  • Option overrides at different scopes: per-subnet, per-host, etc. including DNS-related options
  • Supports custom DHCP option definitions (integer, IP, text, arrays, domain names)
  • Option extensions-path to load additional option definitions from external files
  • Interface binding (specify which network interfaces the server should listen on)

Address handling, conflict & reclamation

  • ICMP Echo (ping) check before assigning addresses to detect conflicts
  • Abandoned addresses marking (if a ping responds, the address is marked abandoned and not reused until safe)
  • Reclaiming abandoned addresses when needed, with re-check via ICMP Echo

DHCP client

  • dhclient implements DHCPv4 and DHCPv6 client modes via -4/-6 commandline switches
  • Tracks client leases persistently via dhclient.leases file with compaction
  • Fallback to old leases if no server is reachable (if still valid)
  • Automates interface reconfiguration (processing of BOUND, RENEW, REBIND, REBOOT, EXPIRE, STOP, RELEASE states via dhclient-script)
  • dhclient-script writes a new /etc/resolv.conf file, sets default routes, static routes, address aliases, etc.
  • Supports alias IP configuration with prefixed variables

DHCP relay, failover & high-availability

  • DHCP relay agent (dhcrelay) to forward DHCP/BOOTP across network segments
  • Failover support between DHCP servers, synchronizing lease state and enabling redundancy
  • OMAPI/runtime management of failover state and unacknowledged updates

DNS UPDATE / dynamic DNS integration

  • Supports performing automatic DNS updates to A and PTR records upon lease events (assignment, renewal, expiration, release)
  • Secure DNS updates using authentication (e.g. TSIG or similar)
  • Ability to disable DNS updates (ddns-update-style none)
  • Handles conflicting DNS records, stale entries cleanup, update policies
  • Opens random UDP ports for DNS UPDATE operations when enabled (for both IPv4 and IPv6)
  • OMAPI / omshell allows inspection/modification of DNS-related attributes in lease/host objects (e.g. client-hostname)

OMAPI runtime management & scripting

  • Use OMAPI (e.g., omshell) to inspect and control DHCP objects (leases, hosts, groups, failover) at runtime
  • Modify host/lease attributes (e.g. hostname, addresses) without restarting the DHCP server
  • Host/group declarations may embed executable statements influencing DHCP/DNS logic
  • Event hooks tied to lease lifecycle (assign, renew, release, expire) can be used to trigger external actions or scripts

Other features

  • Writes leases frequently to disk to prevent data loss even across crashes
  • Lease file compaction / rewriting (rolling over large lease files) to avoid unbounded size growth
  • Logging / tracing support for debugging (including DNS update logs)
  • Support for Client FQDN suboptions (hostname/domain handling in DHCP)
  • Relay Agent Information (option 82) support
  • IPv4-over-IPv6 DHCP support (DHCPv4 over DHCPv6 encapsulation) via -4o6 mode

Lease installation

Lease software packages are available for the following operating system platforms:

To install Lease version 1.99.7 on Red Hat Enterprise Linux 10 (x86_64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-epel and akira-epel-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/epel/testing/10/x86_64/akira-release-1.99.7.20250831123527.772ce56e35-1.el10.noarch.rpm

Then, enable the akira-epel-testing DNF repository:

# dnf config-manager setopt akira-epel-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Red Hat Enterprise Linux 10 (aarch64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-epel and akira-epel-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/epel/testing/10/aarch64/akira-release-1.99.7.20250831123527.772ce56e35-1.el10.noarch.rpm

Then, enable the akira-epel-testing DNF repository:

# dnf config-manager setopt akira-epel-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Red Hat Enterprise Linux 9 (x86_64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-epel and akira-epel-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/epel/testing/9/x86_64/akira-release-1.99.7.20250831123527.772ce56e35-1.el9.noarch.rpm

Then, enable the akira-epel-testing DNF repository:

# dnf config-manager setopt akira-epel-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Red Hat Enterprise Linux 9 (aarch64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-epel and akira-epel-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/epel/testing/9/aarch64/akira-release-1.99.7.20250831123527.772ce56e35-1.el9.noarch.rpm

Then, enable the akira-epel-testing DNF repository:

# dnf config-manager setopt akira-epel-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Red Hat Enterprise Linux 8 (x86_64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-epel and akira-epel-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/epel/testing/8/x86_64/akira-release-1.99.7.20250831123527.772ce56e35-1.el8.noarch.rpm

Then, enable the akira-epel-testing DNF repository:

# dnf config-manager setopt akira-epel-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Red Hat Enterprise Linux 8 (aarch64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-epel and akira-epel-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/epel/testing/8/aarch64/akira-release-1.99.7.20250831123527.772ce56e35-1.el8.noarch.rpm

Then, enable the akira-epel-testing DNF repository:

# dnf config-manager setopt akira-epel-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Fedora Linux 42 (x86_64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-fedora and akira-fedora-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/fedora/testing/42/x86_64/akira-release-1.99.7.20250831123527.772ce56e35-1.fc42.noarch.rpm

Then, enable the akira-fedora-testing DNF repository:

# dnf config-manager setopt akira-fedora-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Fedora Linux 42 (aarch64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-fedora and akira-fedora-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/fedora/testing/42/aarch64/akira-release-1.99.7.20250831123527.772ce56e35-1.fc42.noarch.rpm

Then, enable the akira-fedora-testing DNF repository:

# dnf config-manager setopt akira-fedora-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Fedora Linux 41 (x86_64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-fedora and akira-fedora-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/fedora/testing/41/x86_64/akira-release-1.99.7.20250831123527.772ce56e35-1.fc41.noarch.rpm

Then, enable the akira-fedora-testing DNF repository:

# dnf config-manager setopt akira-fedora-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

To install Lease version 1.99.7 on Fedora Linux 41 (aarch64), follow these steps as the root user.

First, install the akira-release RPM package that will add the akira-fedora and akira-fedora-testing DNF repositories to your system, as well as associated GPG keys used to verify signed RPM packages from these repositories:

# dnf install https://download.banu.com/packages/akira/1.99/fedora/testing/41/aarch64/akira-release-1.99.7.20250831123527.772ce56e35-1.fc41.noarch.rpm

Then, enable the akira-fedora-testing DNF repository:

# dnf config-manager setopt akira-fedora-testing.enabled=1

Then, install the lease RPM package that will install the Lease software and documentation:

# dnf install lease

Then, if you wish to run the DHCP servers, configure them suitably by editing /etc/lease/dhcpd.conf and /etc/lease/dhcpd6.conf, and then run them:

# systemctl enable --now dhcpd
# systemctl enable --now dhcpd6

Lease documentation

Lease is documented in the Lease User Manual, and manpages are provided for the Lease programs and their config files. The user manual and manpages are also included in the software packages.

Branch Type User Manual User Manual Download HTML README License
1.99 Development View PDF View HTML Download HTML ZIP View README View LICENSE.txt

Lease support

  • To report a bug in the product, please email <lease-bugs@banu.com> with detailed information about the issue. Please include sufficient information to allow reproduction of the problem by us.
  • Personal users of Lease may email the Lease mailing lists for support. Please see the mailing lists instructions on how to use the lists.
  • Commercial users of Lease should follow the instructions provided to them for creating support tickets.