XCAT_2.18.2_Release_Notes

xCAT 2.18.2 Release Notes (August 1, 2026)

xCAT 2.18.2 is a maintenance release for the 2.18 series. It includes the changes from the interim 2.18.1 Enterprise Linux snapshot, which did not have a separate GitHub release. These notes cover the full change set since 2.18.0.

Operating System Support

This maintenance release does not change the operating system support matrix introduced with xCAT 2.18.0.

Complete OS support details are available in the xCAT2 Release Information and the Compute node support matrix documentation.

Platform	Arch
EL8	x86_64, ppc64le
EL9	x86_64, ppc64le
EL10	x86_64, ppc64le
Ubuntu 22.04 LTS	x86_64, ppc64el
Ubuntu 24.04 LTS	x86_64, ppc64el
Ubuntu 26.04 LTS	x86_64, ppc64el

Highlighted Changes

DHCP, DNS & network boot

• Restore makedhcp -n replacement behavior with Kea — as with ISC DHCP, the command writes a fresh configuration without importing old reservations and saves the previous active configuration as .xcatbak. Run makedhcp -a or makedhcp <noderange> afterward to populate the required reservations.
• Kea reservation reliability — unresolved hostnames no longer abandon otherwise valid nodes, NICs marked *NOIP* are skipped, and failed live updates do not leave generated and active configurations out of sync. See #7704, #7707, and #7709.
• Kea platform handling — use configured runtime paths for control sockets and the service account; select the Ubuntu backend from the full release number. See #7695 and #7697.
• DNS updates — new installations on EL9 or later and Ubuntu 20.04 or later use HMAC-SHA256 for TSIG. Existing installations keep their configured algorithm. DDNS retries transient failures, reports persistent failures, and recognizes routed local nameserver addresses. See #7653 and #7658.
• Network boot fixes — UEFI clients reporting architecture 00:07 receive the correct loader; IPv6 reverse-zone generation no longer loops indefinitely; Kea uses the shared MAC normalization logic. See #7659, #7683, and #7679.

Provisioning & networking

• Ubuntu Subiquity profiles include an identity section, support an online apt mirror, generate match-by-MAC netplan configuration, and do not copy the image builder's machine identity into diskless images.
• Add the missing EL8 and EL9 ppc64le netboot templates, generate pseries virtual machines on ppc64le hypervisors, and use tmux with virsh for KVM serial consoles.
• Genesis package upgrades work across usr-merged filesystems and older xCAT installations. Link detection is bounded, and the fixed startup delay is limited to ppc64le systems.
• mknb avoids transient discovery addresses and publishes the Genesis image atomically, preventing concurrent invocations from exposing a partial image. See #7681.

Packaging, build & service management

• buildrpms.pl builds a signed, self-contained, multi-architecture core repository. It initializes mock roots, serializes conflicting target builds, propagates worker failures, and does not sign partial output. See #7700.
• RPM and Debian package upgrades preserve xcatd's SysV or systemd state, including custom runlevels and locally managed init scripts. See #7685.
• go-xcat no longer aborts when a repository contains obsolete or unavailable packages. See #7613.
• The 2.18 GitHub workflow runs every source unit test instead of a hand-maintained subset. See #7686.

Other fixes

• nodech accepts comma-delimited values with the ,= and ^= operators.
• makehosts indexes host lookups. IPv6 route parsing ignores link-local and non-route lines, and formatNetmask handles an undefined mask.
• rcons, replaycons, and tcons work with resolved conserver addresses, Confluent console selection, and current tmux releases.
• xcatprobe uses ss for listener checks and reports command failures rather than silently treating them as closed ports.
• copycds keeps SLE 15 source media in separate slots, and IPMI suite 3 authentication retries a zero-length RAKP2 HMAC response.

Download xCAT

xCAT 2.18.2 for Enterprise Linux 8, 9, and 10 is available from the signed yum repositories:

• xcat-core: https://xcat.org/files/xcat/repos/yum/2.18/xcat-core/
• xcat-dep/rh10: https://xcat.org/files/xcat/repos/yum/latest/xcat-dep/rh10/
• xcat-dep/rh9: https://xcat.org/files/xcat/repos/yum/latest/xcat-dep/rh9/
• xcat-dep/rh8: https://xcat.org/files/xcat/repos/yum/latest/xcat-dep/rh8/

Example /etc/yum.repos.d/xcat-core.repo:

[xcat-core]
name=xCAT 2.18 Core
baseurl=https://xcat.org/files/xcat/repos/yum/2.18/xcat-core/
enabled=1
gpgcheck=1
gpgkey=https://xcat.org/files/xcat/repos/yum/2.18/xcat-core/repodata/repomd.xml.key

Then:

dnf clean all
dnf install xCAT

The signed source tag and GitHub-generated source archives are available on the xCAT 2.18.2 release page. The complete source change set is in the 2.18.0...2.18.2 comparison.

Offline tarball bundles

No 2.18.2 offline tarball bundle was published with this GitHub release. Use the signed yum repositories above or the source archives from GitHub.

Key Issues Resolved

Pull Requests included in xCAT 2.18.2

Documentation

Complete documentation is hosted at https://xcat-docs.readthedocs.io/.