RHEL 10+ Knowledge Patch
Claude's baseline knowledge covers RHEL through 9.3. This skill provides changes from RHEL 10.0 (2025-06-10) onwards.
Breaking Changes Quick Reference
| What Changed | Old (RHEL 9) | New (RHEL 10+) |
|--------------|-------------|----------------|
| Redis | redis package | Removed — use valkey 7.2 |
| Sendmail | sendmail package | Removed — use postfix |
| DHCP server | dhcp/dhclient | Removed — use dhcpcd or ISC Kea |
| Network teaming | teamd/libteam | Removed — use bonding |
| FIPS setup | fips-mode-setup | Removed — enable at install with fips=1 kernel arg |
| FIPS check | /etc/system-fips | Removed — read /proc/sys/crypto/fips_enabled |
| TLS crypto policy | RSA key exchange allowed | RSA key exchange rejected in DEFAULT policy |
| SHA-1 in TLS | Allowed in LEGACY | Disallowed even in LEGACY policy |
| OpenSSL Engines | ENGINE API available | Removed — use providers (e.g. pkcs11-provider) |
| CA trust bundle | /etc/pki/tls/certs/ca-bundle.crt | /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem |
| Installer remote | VNC (inst.vnc) | RDP (inst.rdp, inst.rdp.password) |
| Default user privs | Non-admin | Admin by default |
| GFS2 | Supported | Removed |
| Container cgroups | v1 default | v2 default |
| Rootless networking | slirp4netns | pasta |
Software Versions (RHEL 10.0)
Python 3.12, Ruby 3.3, Node.js 22, Perl 5.40, PHP 8.3, GCC 14.2, glibc 2.39, LLVM 19.1.7, Rust 1.84.1, Go 1.23, MariaDB 10.11, MySQL 8.4, PostgreSQL 16, Valkey 7.2, Apache 2.4.62, nginx 1.26, Git 2.45, OpenSSH 9.9, GnuTLS 3.8.9.
RHEL 10.1 adds: GCC Toolset 15, Python 3.13 (alternate AppStream).
Podman v5 Changes
Podman v5 is the default in RHEL 10. Key differences from v4:
pastais default rootless network (notslirp4netns)- cgroups v2 only (v1 no longer default)
podman farm buildfully supported for multi-arch images- Quadlets support pods (
.podfiles) podman updatechanges are persistent (SQLite and BoltDB backends)containers.confis read-only for connections/farms — usepodman.connections.json--compat-volumesoption for builds (VOLUME instruction handling)zstd:chunkedcompression for push/pull- sigstore signatures replace GPG for image verification
See references/podman-v5.md for Quadlet keys and CLI option details.
Security and Crypto Policy
RHEL 10 makes significant crypto policy changes:
- DEFAULT policy rejects TLS ciphers with RSA key exchange (use LEGACY to re-enable)
- LEGACY policy disallows SHA-1 signatures in TLS
- DSA and SEED algorithms removed from NSS
- RSA PKCS#1 v1.5 encryption deprecated in GnuTLS
- Post-quantum algorithms (PQ) available as Technology Preview via crypto-policies
- Sequoia PGP tools
sqandsqvcomplement GnuPG - OpenSSL ENGINE API removed — migrate to
pkcs11-provider - HeartBeat and SRP removed from TLS
See references/security-changes.md for details.
OpenSSH 9.9
- Ed25519 keys generated by default (except FIPS mode — defaults to RSA)
ChannelTimeoutkeyword insshd_configfor inactive channel closureEnableEscapeCommandlineoption inssh_config- Agent key restriction and forwarding controls
Removed Infrastructure
# These packages no longer exist in RHEL 10:
# sendmail → postfix
# redis → valkey
# dhcp/dhclient → dhcpcd or ISC Kea
# teamd/libteam → use bonding
# fips-mode-setup → fips=1 kernel arg at install
# scap-workbench → oscap CLI
# oscap-anaconda-addon → RHEL image builder OpenSCAP integration
See references/removed-features.md for the full list.
Installer Changes
- RDP replaces VNC:
inst.rdp,inst.rdp.password,inst.rdp.username - Wayland compositor replaces Xorg in installer (
inst.xdriverremoved) - No separate
/bootpartition on disk images - New users get admin privileges by default
- Kickstart:
--teamslaves/--teamconfigremoved (use--bondslaves/--bondopts) - Kickstart:
auth/authconfigremoved (useauthselect) - Kickstart:
timezone --ntpserversremoved (usetimesource --ntp-server)