Anish, That's correct, the broker will down convert messages for older consumers after log.message.format.version is increased. As I said, however, this has an impact on efficiency so you should only do it if the traffic from old consumers is low (as mentioned in the release notes). Also note that you _cannot_ safely downgrade log.message.format.version. If you do that, you will get errors.
Ismael On Wed, Nov 22, 2017 at 10:13 AM, Anish Mashankar <[email protected]> wrote: > Thanks Ismael. > Just need a clarification on something because I observed getting errors > from the v0.9 and v0.10 consumer for invalid message format. > Is it true that after bumping the consumer version post rolling upgrade > will not cause message format mismatch errors in the Consumer? > > On Tue, Nov 21, 2017 at 7:37 PM Ismael Juma <[email protected]> wrote: > > > Hi Anish, > > > > The documentation is a bit misleading, see the following JIRA: > > > > https://issues.apache.org/jira/browse/KAFKA-6238 > > > > All of your clients will still work after the upgrade, but there is an > > efficiency hit if the message format used for the topic is newer than the > > message format supported by the consumer. > > > > Also, we found a memory leak in 1.0.0, so I'd recommend you upgrade to > > 0.11.0.2 or wait until 1.0.1. > > > > Ismael > > > > On Tue, Nov 21, 2017 at 8:54 AM, Anish Mashankar < > [email protected] > > > > > wrote: > > > > > Hello Kafka users! > > > The first question that I have is related to the documentation. I see > > that > > > we no longer have to change the message format version when upgrading > to > > > 1.0. So, will all clients continue to work after performing the rolling > > > upgrade? > > > We are running Kafka v0.10.0.0. The Kafka ecosystem consists of several > > > nodejs producer-consumers (NoKafka library which using v0.9 and v0.10 > > > protocols), few kafka connect projects (v0.10.2) and a java consumer > > > running on v0.8 library. Which of the applications can I expect to > break > > > after the rolling upgrade due to mismatch in protocol versions? > > > Also, I see the quote in the documentation saying that if downtimes > were > > > acceptable, we need not go through changing the protocol versions and > > only > > > update the code. Does this mean even older clients will have no > problems > > > connecting to the brokers post upgrade? > > > -- > > > > > > Regards, > > > > > > Anish Samir Mashankar > > > > > > Site Reliability Engineer > > > > > > VIMANA > > > > > > Phone: +91-9789870733 <+91%2097898%2070733> > > > > > > -- > > Regards, > > Anish Samir Mashankar > > Site Reliability Engineer > > VIMANA > > Phone: +91-9789870733 >
