Re: Feature request: A method to configure client-side TLS ciphers for streaming replication

On Tue, Aug 26, 2025 at 9:09 AM xx Z <xxz030811(at)gmail(dot)com> wrote:

> Hello,
> Thank you for the reply and for the advice about our PostgreSQL version.
> We will plan to update it.
> To clarify what I meant by "standby (client)": In a streaming replication
> setup, the standby server connects to the primary server to receive data.
> In this specific network connection, the standby acts as the client, and
> the primary acts as the server.
>

I think you are using non-standard terminology.

> My question is about restrict thr lists of supported TLS ciphers on the
> standby (the client side of the connection).
> Regarding my original question, does the latest version of PostgreSQL
> provide a way to configure the client-side TLS cipher list for the
> replication connection? If not, are there any discussions or plans to add
> this feature in the future?
>

That's the responsibility of your ssl configuration, I think.

https://www.postgresql.org/message-id/39BE74F7-903A-467F-AA15-E7062361A8E2%40yesql.se

>
> Ron Johnson <ronljohnsonjr(at)gmail(dot)com>于2025年8月26日 周二21:00写道：
>
>> On Tue, Aug 26, 2025 at 3:28 AM xx Z <xxz030811(at)gmail(dot)com> wrote:
>>
>>> Hello PostgreSQL community,
>>>
>>> I have a question regarding the configuration of streaming replication.
>>>
>>> When setting up streaming replication over TLS, I've noticed that while
>>> the primary server can restrict its supported encryption algorithms using
>>> the ssl_ciphers parameter, there doesn't seem to be a corresponding method
>>> for the standby (client) side of the replication connection. The standby
>>> appears to use all the default ciphers supported by the system's OpenSSL
>>> library.
>>>
>>
>> What is a "standby (client)"?
>>
>> Postgresql version: 15.2
>>>
>>
>> That's missing 12 sets (three years) of bug fixes. When using RPM or
>> .deb packages, updating takes only a few minutes.
>>
>

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