Outgoing Email Queue Stuck

Question

Hi everyone,

We're running Jira Service Management / Software Data Center 10.3.8, and outgoing emails keep getting stuck in the mail queue, only going out after a manual queue flush.

In the logs we consistently see:

Caused by: com.sun.mail.smtp.SMTPSendFailedException: 421 4.4.2 Message submission rate for this client has exceeded the configured limit

We've already checked the SMTP server rate limits (Receive Connector MessageRateLimit) and confirmed there's no issue there — it's set to Unlimited.

Has anyone else run into this issue on 10.3.8? Any insight would be appreciated.

Thanks!

Gabriela - LeanZero · Answer

Hi @Mariam Hovhannisyan, yes, and on that exact version. JRASERVER-79037, mail queue piling up after upgrading to 10.3.8+, filed against 10.3.8, 10.3.9 and 10.3.12. Atlassian puts it down to JRASERVER-78861, the 10.3.8 change that had Jira cache the SMTP connection instead of opening one for every message. Your flush working fits that. The server takes them fine once something hands them over.

Workaround is on the ticket, from Atlassian. Add com.atlassian.jira.smtp.transport.cache.disabled at <BASE_URL>/secure/admin/SiteDarkFeatures!default.jspa. It's reversible. Two admins on 10.3.12 and 10.3.13 say it cured them, one says it did nothing. Closed Cannot Reproduce, but an Atlassian comment on it says they accept the bug is real. No 421 in it though, so I can't call it your cause.

Unlimited doesn't close the Exchange side either. MessageRateLimit is per receive connector, and Exchange creates several by default. Client Frontend on 587 and Client Proxy on 465 both ship at 5 a minute. Get-ReceiveConnector | Format-List Name,Bindings,RemoteIPRanges,TransportRole,MessageRate* to see which one Jira lands on.

Marc -Devoteam- · Answer

Hi @Mariam Hovhannisyan

See following KB articles on things to check;

* troubleshooting-slow-stuck-notification-issues-in-jira-or-jira-service-management-server 
* outgoing-smtp-not-sending-out-mail 
* health-check-mail-queue 
* jira-notifications-piling-up-in-the-mail-queue-due-to-smtp-server-infinite-timeout-setting

Most likely the information will be found in the log files, but the links can give you pointers where to look.

Or it's related to the mail server used for sending mail, this will also be in the links.

Gor Greyan · Answer

@Mariam Hovhannisyan

Hi Mar jan,

We're seeing very similar behavior in our Jira Data Center environment as well.

It may be worth checking whether there are any SMTP/Exchange throttling policies beyond the Receive Connector MessageRateLimit that could affect client submissions.

We are planning to update the version to the latest LTS version; hope the issue will not occur there.