[LOG4J2-2829] TcpSocketManager.write swallows IOException when retry = false or reconnector != null

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.12.1
• Fix Version/s: 2.15.0
• Component/s: Appenders
• Assignee: Unassigned
• Reporter: Mihail
• Created: 24/Apr/20 15:38
• Updated: 02/Nov/21 18:55
• Resolved: 24/Oct/21 19:30

Description

Hi, I see very stange behavior when using tcp SocketAppender. My configuration is:

<Socket name="auditSocket" protocol="TCP" host="10.8.84.194" port="4587" connectTimeoutMillis="10000" reconnectionDelayMillis="10000"
immediateFail="true" immediateFlush="true" ignoreExceptions="false" bufferedIO="false">

After application starts and before writing any logs I simulate connection reset with:

iptables -A OUTPUT -p tcp -d 10.8.84.194 --dport 4587 -j REJECT --reject-with tcp-reset

Now the strange part:

1. First log is written to output stream successfully (but nothing actually gets sent)
2. Second log throws IOException on outputstream write, this gets handled with a reconnection attempt (which fails) and result is AppenderLoggingException - this is what I expect because I'm using a failover appender to route the log into file.
3. Third and subsequent log attempts also fail due to IOException on outputstream write BUT no AppenderLoggingException is raised - reconnector is not null at this point and IOException gets swallowed up.

 

I'm using log4j2 2.12.1

 

 

Issue Links

• links to: GitHub Pull Request #591