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After upgrade to fwupd­-2.0.­19-2.­el9_8­, the TPM2 is no longer found

VerifiedUpdated on Oct 10, 2026Subscription required

After upgrade to fwupd­-2.0.­19-2.­el9_8­, the TPM2 is no longer found: ~~~ # fwupdmgr security WARNING: UEFI capsule updates not available or enabled in firmware setup See https­://gi­thub.­com/f­wupd/­fwupd­/wiki­/Plug­inFla­g:cap­sules­-unsu­pport­ed for more information. Host Security ID: HSI:I­NVALI­D:cha­ssis[­rack-­mount­] (v2.0.19) HSI-1 ✔ Platform debugging: Disabled ✔ Supported CPU: Valid ✔ UEFI bootservice variables: Locked ✔ UEFI platform key: Valid ✘ BIOS firmware updates: Disabled ✘ SPI write: Not found ✘ SPI lock: Not found ✘ SPI BIOS region: Not found ✘ TPM v2.0: Not found <------- [..] ~~~ This worked on `fwup­d-1.9­.31-1­.el9`­, which was part of RHEL9.6GA.

Solution

OpenShift Virtual Machine live migration hangs or never completes

VerifiedUpdated on Oct 10, 2026Subscription required

- Live Migration of Virtual Machine is stuck at 99%.- Live Migration of Virtual Machine never completes.- `DataRemaining` and `MemoryRemaining` continues to fluctuate up and down.- `Live migration abort detected with reason: Live migration stuck for XXX sec`.

Solution

RT task starved by repeated RT push and stopper retries on RHEL9-based kernel-rt, even with the CVE-2026-45919 fix

VerifiedUpdated on Oct 10, 2026Subscription required

+ On RHEL9 kernel-rt, a latency-sensitive RT application can miss its deadlines, hit its own watchdog timeout and crash, because one of its critical RT tasks is starved of CPU time. + [An earlier form of this probl­em](h­ttps:­//acc­ess.r­edhat­.com/­solut­ions/­71469­61) was fixed upstream by commit [9489­4c9c4­77e](­https­://gi­t.ker­nel.o­rg/pu­b/scm­/linu­x/ker­nel/g­it/to­rvald­s/lin­ux.gi­t/com­mit/?­id=94­894c9­c477e­53bce­a052e­075c5­3f89d­f3d2a­33e) ([CVE­-2026­-4591­9](ht­tps:/­/acce­ss.re­dhat.­com/s­ecuri­ty/cv­e/cve­-2026­-4591­9)), and our JIRAs, RHEL-240634 (9.8.z) and RHEL-244409 (9.6.z), addressed the backport of that fix to RHEL9. + However, a slightly different issue remains after applying 94894c9c477e. A migration-disabled RT task cannot be pushed to another CPU, but the scheduler keeps retrying the push as long as that task stays at the head of the pushable list. Each retry wakes the stopper thread, which takes the CPU away from the RT task running there, and the next retry follows right after. + The sequence looks like this in ftrace, with kprobes on the RT balancer (pnpt is the return of pick_­next_­pusha­ble_t­ask()­, socn is stop_­one_c­pu_no­wait(­), pcs is push_cpu_stop(), flr_ent and flr_ret are the entry and return of find_­lock_­lowes­t_rq(­), pullrt is pull_rt_task(), and md is the task's migration_disabled count). ~~~ threadB-71804 [022] d..h2.. 49483.514458: pnpt: (push­_rt_t­ask.p­art.0­+0x1e­/0x3f­0 <- pick_­next_­pusha­ble_t­ask) task=­0xff1­b7f96­80228­000 pid=2001078 comm=­"­;thre­adA&q­uot; md=2 prio=49 threadB-71804 [022] d..h2.. 49483.514461: socn: (stop­_one_­cpu_n­owait­+0x0/­0x40) tgtcpu=22 pid=71804 comm=­"­;thre­adB&q­uot; prio=49 md=0 <...>-246 [022] d..h3.. 49483.514473: pnpt: (push­_rt_t­ask.p­art.0­+0x1e­/0x3f­0 <- pick_­next_­pusha­ble_t­ask) task=­0xff1­b7f96­80228­000 pid=2001078 comm=­"­;thre­adA&q­uot; md=2 prio=49 <...>-246 [022]....2.. 49483.514480: pcs: (push­_cpu_­stop+­0x0/0­x210) task=­0xff1­b7f99­e5f44­680 pid=71804 comm=­"­;thre­adB&q­uot; prio=49 md=0 oncpu=0 onrq=1 ncpus=30 <...>-246 [022] d...4.. 49483.514481: flr_ent: (find­_lock­_lowe­st_rq­+0x0/­0x150­) pid=71804 comm=­"­;thre­adB&q­uot; prio=49 md=0 oncpu=0 onrq=1 tcpu=22 ncpus=30 srccpu=22 <...>-246 [022] d...5.. 49483.514489: pnpt: (find­_lock­_lowe­st_rq­+0x98­/0x15­0 <- pick_­next_­pusha­ble_t­ask) task=­0xff1­b7f96­80228­000 pid=2001078 comm=­"­;thre­adA&q­uot; md=2 prio=49 <...>-246 [022] d...4.. 49483.514489: flr_ret: (push­_cpu_­stop+­0x118­/0x21­0 <- find_lock_lowest_rq) ret=0x0 dest=33620255 <...>-246 [022] d..h4.. 49483.514490: pnpt: (push­_rt_t­ask.p­art.0­+0x1e­/0x3f­0 <- pick_­next_­pusha­ble_t­ask) task=­0xff1­b7f96­80228­000 pid=2001078 comm=­"­;thre­adA&q­uot; md=2 prio=49 <...>-246 [022] d...3.. 49483.514493: pullrt: (pull­_rt_t­ask+0­x0/0x­450) rqcpu=22 ~~~ + The head of the pushable list is threadA with md=2 (inside 2 nested migrate_disable() regions), so it cannot be pushed. push_rt_task() falls back to pushing the running task (rq-> curr), threadB, and wakes the stopper (socn). + The stopper, pid 246, runs push_cpu_stop() for threadB, but after taking the locks the check picks the head again and gets threadA, not threadB, so the push is refused (flr_ret ret=0x0). + On the way back pull_rt_task() runs and the next retry starts. In this capture covering 89 ms, push_cpu_stop() ran 5,204 times and every one of those pushes was refused. + As a result, the RT task running on that CPU gets very little CPU time, and the application watchdog eventually fires. + The 94894c9c477e fix does not cover this remaining case.

Solution

Troubleshooting Red Hat Data Grid Operator 8.6.0 Upgrade Issue: Stuck at old version 8.5.12

VerifiedUpdated on Oct 10, 2026Subscription required

* Upgrade process reports success, but the product version remains at 8.5.12 * Update channel is configured to 8.6.0, however the product version does not change from 8.5.12

Solution

Unable to View Storage Backend Capacity and PVC Utilization for VMs in RHOCP 4 console

VerifiedUpdated on Oct 10, 2026Subscription required

* Unable to view storage backend capacity and Persistent Volume Claim utilization in the OpenShift console. * The `Used` column in the PVC list view displays- (no value) for all PVCs, including those attached to virtual machines. * Prometheus metrics, such as `kube­let_v­olume­_stat­s_use­d_byt­es`, return `0` or `No datapoints found`, preventing from monitoring PVC usage and storage consumption.

Solution

Customize br-ex interface using NMState in OpenShift 4.16+

VerifiedUpdated on Oct 9, 2026Subscription required

- Customize br-ex interface using NMState in OpenShift 4.16+- Modify br-ex in Day 2 operation

Solution

OpenShift 4: Day-2 Methods for Network configuration

Updated on Oct 9, 2026Subscription required

- What are the supported and available methods for networking configuration changes on nodes running in OpenShift 4?- How can I modify a node networking configuration in a supported way on OpenShift 4?- What methods can be used to update networking on nodes as a day 2 operation on OpenShift 4?- Is nmcli/nmtui supported on Red Hat CoreOS nodes or OpenShift 4?- How can I set a custom route on OpenShift 4?- How can I modify DNS on OpenShift 4?- How can I modify NTP on OpenShift 4?- How can I move to a Static IP configuration on OpenShift 4?- What restrictions exist for networking on OpenShift 4?- How can I modify the MTU or network configuration of br-ex? Environment:- Red Hat OpenShift Container Platform (RHOCP) 4- Red Hat CoreOS (RHCOS)- Red Hat Enterprise Linux (RHEL) # Index:- [Overview of networking decla­rativ­ely](­#over­view)­- [Frequently Asked Questions](#FAQ)- [Limitations and Restr­ictio­ns](#­limit­ation­s)- [Change the default Selection Logic for br-ex­](#br­-ex-t­arget­)- [DHCP to Static conve­rsion­s](#d­hcp_t­o_sta­tic)- [Machine Confi­g](#m­achin­e_con­fig)- [NMState Operator](#nmstate)- [Customize br-ex using Nmsta­te](#­custo­mized­_br-e­x)- [NMCLI/manual update](#nmcli)- [Custom route injec­tion/­confi­gurat­ion](­#rout­es)- [DNS confi­gurat­ions]­(#dns­)- [NTP updates](#NTP)- [Kernel arguments updates](#karg)

Article

OCP4: MTU Migration flow does not tolerate customized br-ex configuration and will fail

In progressUpdated on Oct 9, 2026Subscription required

On OpenShift 4, if using the [customized br-ex­](htt­ps://­acces­s.red­hat.c­om/so­lutio­ns/71­11563­) configuration, and subsequently attempting to run the MTU migration script, the process will abort and degrade the platform due to missing expected variables in the mtu-migration.sh script.

Solution
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The "sssctl domain-list" command is not showing AD Global Catalog servers.

VerifiedUpdated on Oct 8, 2026Subscription required

The `sssctl domain-list` command is not showing AD Global Catalog servers. i.e: ~~~ [root@host ~]# sssctl domain-status example.com Online status: Online Active servers: AD Global Catalog: not connected AD Domain Controller: ad1.example.com Discovered AD Global Catalog servers: None so far. Discovered AD Domain Controller servers: - ad1.example.com - ad2.example.com - ad3.example.com ~~~

Machine Using KPatch-Patch Still Showing As Vulnerable In Red Hat Insights

VerifiedUpdated on Oct 9, 2026Subscription required

+ A server registered to Red Hat Insights is shown to be vulnerable to a Common Vulnerabilities and Exposures (CVE), despite having and using a kpatch-patch to address the vulnerability. + Example: A stock RHEL 7.9 server registered to Red Hat Insights is shown to be vulnerable to [CVE-2022-32250](https://access.redhat.com/security/cve/CVE-2022-32250).  That CVE is addressed by either a [kernel update](https://access.redhat.com/errata/RHSA-2022:5232) or a [kpatch-patch](https://access.redhat.com/errata/RHSA-2022:5216). The day after applying the kpatch-patch, Red Hat Insights Inventory still shows the machine (under its Vulnerability tab) vulnerable to that CVE, despite also showing the kpatch-patch RPM installed (under its General Information tab's Installed Packages list).

How to make dnf-automatic.timer setting permanent?

UnverifiedUpdated on Oct 8, 2026Subscription required

- After customizing `/usr/lib/systemd/system/dnf-automatic.timer` to run at a specific day/time the customization works well, but eventually it stops because `/usr/lib/systemd/system/dnf-automatic.timer` goes back to its default. - How to make `/usr/lib/systemd/system/dnf-automatic.timer` changes persistent?

Articles

Technical briefs, reference architectures, and early stages of documentation

Red Hat Case Management - Attachment Service API Guide

Updated on Oct 9, 2026Subscription required

This document is the API usage guide for the Red Hat Case Management Attachment Service. It covers authentication, upload (single part and multipart up to 5 TB), download, deletion, status tracking, and metadata listing for file attachments on Red Hat support cases. The intended audience is developers and integration engineers building clients that interact with the attachment APIs at `https://api.access.redhat.com/support`.

Vmcore analysis techniques

Updated on Oct 6, 2026Subscription required

Tips and tricks used to figure out what caused a system to panic.

Uninstalling an OpenShift cluster

Updated on Sep 28, 2026

Should you need to uninstall an openshift cluster, here are the general instructions for uninstalling a cluster.

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