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Security scan recommends upgrading JWS 6.2 Tomcat 10.1 to Tomcat 10.1.60 for security fixes

VerifiedUpdated on Oct 9, 2026Subscription required

* A security scanner reports CVEs applying to JWS 6.2 Tomcat 10.1 and suggests Tomcat 10.1.60 as the fix

Solution

Configuring Cockpit with httpd reverse proxy

UnverifiedUpdated on Oct 9, 2026Subscription required

- Configuring Cockpit with httpd reverse proxy- How do I add HTTP Strict Transport Security (HSTS) headers to my httpd reverse proxy for Cockpit?

Solution

AJP listener fails to start with UT000220 error after updating to JBoss EAP 7.4.25+ / 8.1 update 8+

VerifiedUpdated on Oct 9, 2026Subscription required

* After updating to JBoss EAP 7.4.25+ or 8.1 update 8+, Undertow AJP listeners fail to start with `UT000220` errors like below: ~~~ ERROR [org.­jboss­.msc.­servi­ce.fa­il] (MSC service thread 1-2) MSC000001: Failed to start service org.w­ildfl­y.und­ertow­.list­ener.­ajp: org.j­boss.­msc.s­ervic­e.Sta­rtExc­eptio­n in service org.w­ildfl­y.und­ertow­.list­ener.­ajp: Failed to start service at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$S­tartT­ask.e­xecut­e(Ser­viceC­ontro­llerI­mpl.j­ava:1­731) at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$C­ontro­llerT­ask.r­un(Se­rvice­Contr­oller­Impl.­java:­1559) at org.j­boss.­threa­ds.Co­ntext­Class­Loade­rSavi­ngRun­nable­.run(­Conte­xtCla­ssLoa­derSa­vingR­unnab­le.ja­va:35­) at org.j­boss.­threa­ds.En­hance­dQueu­eExec­utor.­safeR­un(En­hance­dQueu­eExec­utor.­java:­1990) at org.j­boss.­threa­ds.En­hance­dQueu­eExec­utor$­Threa­dBody­.doRu­nTask­(Enha­ncedQ­ueueE­xecut­or.ja­va:14­86) at org.j­boss.­threa­ds.En­hance­dQueu­eExec­utor$­Threa­dBody­.run(­Enhan­cedQu­eueEx­ecuto­r.jav­a:136­3) at java.­lang.­Threa­d.run­(Thre­ad.ja­va:75­0) Caused by: java.­lang.­Illeg­alArg­ument­Excep­tion: UT000220: The AJP listener is configured to require secret but the secret is either null or empty string. This combination is not allowed. at io.un­derto­w.ser­ver.p­rotoc­ol.aj­p.Ajp­OpenL­isten­er.cr­eateA­jpReq­uestP­arser­(AjpO­penLi­stene­r.jav­a:205­) at io.un­derto­w.ser­ver.p­rotoc­ol.aj­p.Ajp­OpenL­isten­er. (AjpO­penLi­stene­r.jav­a:114­) at org.w­ildfl­y.ext­ensio­n.und­ertow­.AjpL­isten­erSer­vice.­creat­eOpen­Liste­ner(A­jpLis­tener­Servi­ce.ja­va:60­) at org.w­ildfl­y.ext­ensio­n.und­ertow­.List­enerS­ervic­e.sta­rt(Li­stene­rServ­ice.j­ava:1­77) at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$S­tartT­ask.s­tartS­ervic­e(Ser­viceC­ontro­llerI­mpl.j­ava:1­739) at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$S­tartT­ask.e­xecut­e(Ser­viceC­ontro­llerI­mpl.j­ava:1­701).­.. 6 more ERROR [org.­jboss­.as.c­ontro­ller.­manag­ement­-oper­ation­] (Controller Boot Thread) WFLYCTL0013: Operation ("add") failed- address: ([(&q­uot;s­ubsys­tem&q­uot; => "­;unde­rtow&­quot;­), ("server" => "­;defa­ult-s­erver­"­;), (&quo­t;ajp­-list­ener&­quot; => "ajp")])- failure description: {"WFLYCTL0080: Failed services" => {&quo­t;org­.wild­fly.u­ndert­ow.li­stene­r.ajp­"­; => "Failed to start service Caused by: java.­lang.­Illeg­alArg­ument­Excep­tion: UT000220: The AJP listener is configured to require secret but the secret is either null or empty string. This combination is not allowed."}} ~~~ * JBoss EAP 7.4.23 got patched to 7.4.25 and not starting anymore. ~~~ 2026-08-19 08:52:32,170 ERROR [org.­jboss­.msc.­servi­ce.fa­il] (MSC service thread 1-6) MSC000001: Failed to start service org.w­ildfl­y.und­ertow­.list­ener.­ajp: org.j­boss.­msc.s­ervic­e.Sta­rtExc­eptio­n in service org.w­ildfl­y.und­ertow­.list­ener.­ajp: Failed to start service at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$S­tartT­ask.e­xecut­e(Ser­viceC­ontro­llerI­mpl.j­ava:1­731) at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$C­ontro­llerT­ask.r­un(Se­rvice­Contr­oller­Impl.­java:­1559) at org.j­boss.­threa­ds.Co­ntext­Class­Loade­rSavi­ngRun­nable­.run(­Conte­xtCla­ssLoa­derSa­vingR­unnab­le.ja­va:35­) at org.j­boss.­threa­ds.En­hance­dQueu­eExec­utor.­safeR­un(En­hance­dQueu­eExec­utor.­java:­1990) at org.j­boss.­threa­ds.En­hance­dQueu­eExec­utor$­Threa­dBody­.doRu­nTask­(Enha­ncedQ­ueueE­xecut­or.ja­va:14­86) at org.j­boss.­threa­ds.En­hance­dQueu­eExec­utor$­Threa­dBody­.run(­Enhan­cedQu­eueEx­ecuto­r.jav­a:136­3) at java.­lang.­Threa­d.run­(Thre­ad.ja­va:75­0) Caused by: java.­lang.­Illeg­alArg­ument­Excep­tion: UT000220: The AJP listener is configured to require secret but the secret is either null or empty string. This combination is not allowed. at io.un­derto­w.ser­ver.p­rotoc­ol.aj­p.Ajp­OpenL­isten­er.cr­eateA­jpReq­uestP­arser­(AjpO­penLi­stene­r.jav­a:205­) at io.un­derto­w.ser­ver.p­rotoc­ol.aj­p.Ajp­OpenL­isten­er. (AjpO­penLi­stene­r.jav­a:114­) at org.w­ildfl­y.ext­ensio­n.und­ertow­.AjpL­isten­erSer­vice.­creat­eOpen­Liste­ner(A­jpLis­tener­Servi­ce.ja­va:60­) at org.w­ildfl­y.ext­ensio­n.und­ertow­.List­enerS­ervic­e.sta­rt(Li­stene­rServ­ice.j­ava:1­77) at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$S­tartT­ask.s­tartS­ervic­e(Ser­viceC­ontro­llerI­mpl.j­ava:1­739) at org.j­boss.­msc.s­ervic­e.Ser­viceC­ontro­llerI­mpl$S­tartT­ask.e­xecut­e(Ser­viceC­ontro­llerI­mpl.j­ava:1­701).­.. 6 more ~~~

Solution

How to remove the Undertow AJP listener on EAP 7/8?

VerifiedUpdated on Oct 9, 2026Subscription required

* How can the ` ` be removed from EAP 7/8? It is not used and/or not secure.

Solution

How to enable HTTP Strict Transport Security (HSTS) for Cockpit

VerifiedUpdated on Oct 9, 2026Subscription required

- HSTS is required by security scanner. How is it set in `Cockpit` the webservice on port 9090?- How to enable the HTTP Strict Transport Security (HSTS) in Cockpit service?

Solution

Which versions of Red Hat Enterprise Linux have support for the PERC H740P, H745P MX, and H840

VerifiedUpdated on Oct 9, 2026Subscription required

- Which versions of Red Hat Enterprise Linux have support for the PERC H740P, H745P MX, and H840 RAID controllers?

Solution

'blk_update_request: critical nexus error dev dm-X, sector xyz' messages logged in RHEL

VerifiedUpdated on Oct 9, 2026Subscription required

* What is the cause of `critical nexus` errors? * What is a `critical nexus` error? * What is the difference between a `critical nexus` and a `critical target` error? * The following error messages are logged in `/var/log/messages` or `dmesg`: ~~~ kernel: sd 33:0:1:0: reservation conflict kernel: sd 33:0:1:0: [sdc] FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK kernel: sd 33:0:1:0: [sdc] CDB: Read(10) 28 00 ba df ff f8 00 00 08 00 kernel: blk_update_request: critical nexus error, dev sdc, sector 3135242232 kernel: Buffer I/O error on dev sdc, logical block 391905279, async page read ~~~

Solution

How to provide files to Red Hat Support (vmcore, rhev logcollector, sos reports, heap dumps, log files, etc.)

VerifiedUpdated on Oct 9, 2026

* How to provide files to Red Hat Support * Production server crashed, how to attach document, screenshot, crashdump(kdump)? * After hard reboot, collected data like tcpdump, strace, top, ps, vmstat, iostat and reports for analysis. Whom can I send? * System hang and would like to know the reason behind it, where can I provide data for analysis? * How can I attach a file to a Red Hat support case? * Need to upload a file to the support team. * Need to attach a file to a Red Hat support case. * How to provide large files to Red Hat Support (vmcore, rhev logcollector, large sos reports, heap dumps, large log files, etc.) * Customer portal uploader supports uploading of attachments of 250GB each. * The redhat-support-tool supports uploading files 1GB or less only, how to upload large files to Red Hat Technical Support? * How to upload files to Red Hat's Secure FTP (sftp­.acce­ss.re­dhat.­com)?

Solution
Explore articles and solutions that other Red Hat customers are investigating

Solutions

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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 ~~~

I Need a Specific Red Hat Package. Where do I Find it?

UnverifiedUpdated on Oct 8, 2026

* I need to download and install a specific Red Hat package. How do I do that?

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).

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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