Anil Nair wrote it in his MAA Blog Post on April 28: “Oracle is simplifying the software stack by replacing Apache Tomcat application server with Micronaut framework.”. And since some of you asked already, let me give you a bit more information about this change in 19.30 and 19.31 with Grid Infrastructure: Bye Tomcat – welcome Micronaut.
Photo by Hayrullah Gozcu on Unsplash – and I know, the jet in the picture isn’t an F-14 Tomcat 🙂
It happens automatically
At first, no action is needed from your side. This behavior change happens automatically.
It is the default in Grid Infrastructure 26ai, and it got rolled into the 19.31 Grid Infrastrucure and DB Release Updates. To be a bit more precise, you will find the removal of Tomcat happening in 19.31 while the addition of Micronaut happened already in 19.30.
This is being tracked under Bug 34381643 – TRACKING: REMOVE TOMCAT COMPONENT AND FILES FROM 23C GRID HOME. The optional select of Tomcat has been removed. If you still want or need Tomcat, you may need to install it manually by yourself.
Why is this happening?
Quoting Anil, he listed several reasons:
- Lowering exposure to frequently targeted components
- Eliminating the need for a full application server layer
- Reducing overall runtime complexity
And from my own experience, I can tell you that customers always worried about the extra patching effort to keep Tomcat up-to-date by security standards. I read this as a positive move which is the default already in Oracle Grid Infrastructure 23ai/26ai since the beginning, and now happens in 19c as well.
More information
Some of you commented about the inventory not being updated. I learned from internal teams that this is intended, and the exchange of the component does not maintain the inventory. “oracle.tomcat” OUI component is not removed from the inventory. The RU just replaces the tomcat files with micronaut files but cannot modify the inventory. This is expected behavior.
Further Links and Information
–Mike
Hi Mike, what’s a bit confusing to me is that while I can see that no Tomcat/Catalina processes are running after applying the 19.31 GI RU to our ExaCS environmets I still see that there is a fresh TOMCAT patch in my GI Home:
Patch 39107855 : applied on Thu Apr 30 08:40:09 CEST 2026
Unique Patch ID: 28612860
Patch description: “TOMCAT RELEASE UPDATE 19.0.0.0.0 (39107855)”
Created on 20 Apr 2026, 17:48:20 hrs UTC
Even this is installed for just in case someone still needs tomcat it seems like $GI_HOME/tomcat has been purged with the upgrade. What is the purpose of this?
Cheers,
Daniel
Hi Daniel,
my suspicion is that the removal process removes the software/subdirectory but did not update the inventory.
And it looks as if the new RU still has a patch shipped.
But I am checking with Anil Nair right now, and I will update the blog post.
Cheers,
Mike
Good update. Tomcat under grid has been appearing on my vulnerabilities list for a while now.
Proper nerd correction incoming: the plane in the picture is an f18 hornet not an f14 tomcat 😉
Hi James,
I know about the plane – but I did hope that not many would recognize 😀
Thanks 🙂
Mike
Hi Mike,
we have installed 19.31 for the grid infrastructure and the directory $ORACLE_HOME/tomcat does not exist any more indeed.
However, opatch lspatches is still listing the following:
39107855;TOMCAT RELEASE UPDATE 19.0.0.0.0 (39107855)
Regards,
George
Did you patch GI in-place or out-of-place?
Thanks
Mike
we patched GI in-place
I HIGHLY recommend to patch it out of place. Please see Daniel’s detailed blog posts on dohdatabase.com about how to patch GI out-of-place.
Makes life easier.
Cheers,
Mike