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PMTA knowledge base›Block <domain>›Directive§ 3.3.10.53

backoff-to-normal-after

<domain>set by the Hub

After what interval the queue returns to normal mode by itself
in the configuration this is a linebackoff-to-normal-after 1hinside the block <domain>
After how long the queue leaves backoff by itself

The interval after which the queue returns to normal mode regardless of whether there was a successful delivery during that time.

Without this directive there is no way out. The default is “never”: a queue that has once gone into backoff will stay there until the node restarts. This is exactly the reason why “messages stopped going to one domain and did not start again by themselves.”

The main trap. Setting only the exit by time and not the exit by delivery. If the receiver recovers after a minute, the queue will still sit in backoff for the whole interval — an hour or two of lost throughput out of nowhere. The two directives work as a pair.
What the Hub does. It sets both at once: the time from the node preset — two hours in “Careful,” an hour in “Balanced,” half an hour in “Aggressive” — and the return on the first successful delivery. The queue leaves backoff on whichever event comes first. Neither line is written for addresses under warm-up.
Recommended values
Mode Per address (vMTA) In the provider rule When this is your case
Warm-up, cold address 2h — An address younger than 4–6 weeks or back from a pause
Careful 2h — Strict receivers, questionable reputation, the first weeks after warm-up
Balanced default 1h — Normal operation of an established fleet
Aggressive 30m — Warmed-up addresses, friendly receivers, urgent volumes
PowerMTA default never — If the directive is not written at all

An hour or two for the usual case. Enough for the receiving server to change its attitude, and short enough for the queue not to sit in backoff mode all day because of one spike.

Mandatory in a pair with backoff-upon-all-sources-disabled — the manual recommends this directly: the engine does not return the queue to normal mode by itself when the address is enabled again.

The never default means the queue will stay in backoff mode until the service restarts or someone intervenes by hand. On a fleet where mailbox provider rules put queues into backoff, this guarantees a pile-up of slowed-down queues.

The order of magnitude is our recommendation. From the manual here are the never default, the precedence rule for the option in a mailbox provider rule and the recommendation to set it in a pair with backoff-upon-all-sources-disabled.
Example configuration
# without a return the queue stays in backoff mode until a restart
<domain *>
    backoff-to-normal-after 1h    backoff-to-normal-after-delivery yes
</domain>
Two ways back, and they complement each other: by time and by the first successful delivery. Whichever happens first fires.
yellow — — directive names, blue — blocks. They are highlighted the same way in the text of the card.
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Common mistakes and problems

what people get wrong and how it ends2 mistakes▶

Leaving the never default

§ 3.3.10.53

What it costsA queue that gets into backoff mode stays there until the service restarts. On a fleet where mailbox provider rules regularly put queues into backoff, slowed-down queues pile up, and the overall rate drops for no visible reason.
How to spot itThe list of queues has some that sit in backoff for days.
How to do it rightSet a return by time in the general receiver block.

Editing the directive, yet the queue still does not return

§ 3.3.10.53

What it costsIf the queue was put there by a mailbox provider rule with its own backoff-to-normal-after= option, the directive is ignored. The edit goes through without errors and affects nothing.
How to spot itSome queues return on schedule and some do not, with the same configuration.
How to do it rightLook at the mailbox provider rules: the period set in a rule takes precedence.
Compatibility
PowerMTA 6.0
described in the manual of this version · platform: any
The vendor does not state the first version for every directive — there is no note here. The name also appears in the 5.0 edition of the manual.
Reference data
Syntax
backoff-to-normal-after <time-interval>
Values
a time interval or never
Default
never § 3.3.10.53
Applying
reload, no restart needed
Queue
will not touch what is already queued
Where to write it
<domain>
How many times
once in the block
Everything here comes from the manual, with the section.
Inheritance
The value merges across <domain> blocks from general to specific: the best-matching block wins, not the last one in the file. It is ignored if the queue was put into backoff mode by a mailbox provider rule with its own backoff-to-normal-after= option — that one takes precedence. It is picked up by pmta reload.
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Related directives

2 relations

Conflicts with

Parsing receiver responsesA mailbox provider rule can carry its own return period — and then this directive is ignored for that queue. § 3.3.10.53

Applies to

Backoff mode — the queue's second personalityThe mode from which the directive returns the queue on a timer. § 3.3.10.53

Referenced from

backoff-upon-all-sources-disabled<domain>A mandatory pair: without it the queue will not leave backoff, and the vendor recommends setting them together. § 3.3.10.55

How to check on the node
Check not the line but the result: whether queues stay in backoff mode longer than the set period:
pmta show settings hotmail.com/vmta1 | grep -i backoff-to-normal-after
pmta show queues --mode=backoff --maxitems=20
A queue hanging in backoff longer than the set interval is a sign that it was put there by a mailbox provider rule with its own period, and this directive does not apply to it.
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What else to read

3 articles

◇Backoff mode — the queue's second personalityA queue that a receiver has started refusing switches to a parallel set of limits, retries and routes — ten directives that act only in this mode.◇Four value types the whole config is written inBoolean, domain pattern, regular expression and time interval — defined once in § 3.2 and then used by all directives.◇Headers the sender uses to control deliverySix control headers let the submitting side choose a stream, tag a message with a job, set signing options and the key, the envelope identifier and the schedule; each is allowed separately and per source.

In the Hub
Managed at
Configurations → Bounce behavior
Value
The Hub picks it itself — pace, warm-up stage, metrics
Cost of a mistake
reversible: harms only while it is set
Scenarios
Sending address rotation · Tune the pace for a provider
Neighboring settings of the block <domain>:retry-afterbounce-afterbackoff-upon-all-sources-disabledbackoff-retry-afterbackoff-to-normal-after-deliveryAll 135 directives of the block →