Fixed in development branch:
svn://svn.zabbix.com/branches/dev/ZBXNEXT-3581

Successfully tested.

Fixed in:

• pre-4.0.0alpha3 (trunk) r77321

dropped plain text protocol support and made header mandatory; fixed IP fragmentation handling by including header in Zabbix get request, Zabbix server/proxy passive check request and frontend request to Zabbix server

(7) [D] a few suggested documentation improvements :

• in the upgrade notes, it would be useful to mention which zabbix agent versions are not supported now
• compatibility page still says 1.x agents are supported

btw, in the compatibility page, this sentence sounds strange : "Older agents from Zabbix 1.x, 2.x and previous versions of Zabbix 3.x can still be used with Zabbix 4.0"

glebs.ivanovskis You can infer this information from the issue description. But would be nice to have it in Upgrade notes. Also Upgrade notes do not mention complications for self-written senders.

martins-v Thanks, the two mentioned sections updated. Please review. RESOLVED

glebs.ivanovskis, Can we be more specific about the 'complications' you mention? Is there anything that cannot be inferred from the information mentioned in the upgrade notes?

glebs.ivanovskis I like it!
3.0 and 3.4 still have strange "and previous versions" wording. I guess it started with 3.2, where it was supposed to mean that 3.0 and 3.2 (but not 3.4!) agents will work with 3.2 server/proxy.

Speaking of "complications", previously trappers were happily accepting messages without headers as well as messages with headers. Now they will only accept messages with protocol header. We were also thinking about giving examples of generating such header in the most popular languages...

<richlv> looks good indeed, thank you.
noticed a sentence just now :

It generally does not require any configuration changes on the agent side, apart from parameters related to logging for versions before 3.0

this is a bit wrong, as there have been other incompatible config file changes before.

regarding header examples in various languages, examples already abound like :

• http://search.cpan.org/~tex/Zabbix-Sender/lib/Zabbix/Sender.pm
• https://github.com/jbfavre/python-zabbix
• http://zabbix.org/wiki/Docs/protocols/zabbix_sender/1.8/java_example

martins-v Documentation updates:

• Wording of the version compatibility page changed, also in 3.0-3.4. Ideally we would list all incompatible parameter changes (if there are others), but the tracking of those has been somewhat weak.
• The upgrade note entry extended to mention the self-written sender situation.

RESOLVED

glebs.ivanovskis Looks good to me! I've added few snippets loosely based on sources suggested by richlv, Zabbix code and my personal hacks. I hope you are OK with wording and placement.

CLOSED

this has resulted in rather confusing messages during the network discovery : ZBX-13523

Turns out, this change is hitting a lot of users. To possibly help with search results:

Message from ... is missing header. Message ignored.