Hi Chitra, Unsure about whether this will help with your specific requirements or not but have you looked into the REST extension API? Linking to the 3.9.x docs since that's the version you're running but AFAIK the feature hasn't changed much or even at all in a few years: https://kafka.apache.org/39/javadoc/org/apache/kafka/connect/rest/ConnectRestExtension.html
If this doesn't help, I think a KIP could make sense. Cheers, Chris On Wed, Jan 21, 2026, 19:57 Chitra Elangovan <[email protected]> wrote: > Hello Kafka Community, > > I am reaching out to discuss a limitation regarding the Kafka Connect REST > API's embedded Jetty server (we are using kafka 3.9.0 version). > > Currently, the default header size limit is 8KB. In our environment, we are > exceeding this limit due to our business needs. When this limit is > exceeded, Jetty returns a 431 Request Header Fields Too Large error. > > I've noted that while listeners and a few other properties are configurable > via the Worker properties, there doesn't seem to be a straightforward way > to increase the requestHeaderSize for the internal HttpConfiguration. > > Questions for the group: > > - Is there an existing JVM system property or undocumented config that can > override this in the current version? > > - If not, would the community be open to a KIP (Kafka Improvement Proposal) > to expose this as a worker configuration (e.g., > rest.request.header.size.default)? > > - Are there any known workarounds for Kafka Connect distributed workers > without using an external reverse proxy to strip headers?Looking forward to > your insights. > > Best regards, > Chitra Elangovan >
