It seems to related to apache set ups on the origin that were running openssl 1.1.1e since the upgrade to 1.1.1f it seems better  and the SSL_read errors are gone. <br><br><a href="https://github.com/openssl/openssl/issues/11381#issuecomment-607732081">https://github.com/openssl/openssl/issues/11381#issuecomment-607732081</a><br><br>Liam<br><br><br>Sent from ProtonMail mobile<br><br><br><br>-------- Original Message --------<br>On 3 Apr 2020, 07:20, Liam Moncur < liam@moncur.me.uk> wrote:<blockquote class="protonmail_quote"><br><p dir="ltr">We were able to resolve this by enabling proxy_buffering. The root cause for why it started happening is still being investigated.</p>
<p dir="ltr">Thanks,<br>
Liam</p>
<p dir="ltr">Sent with ProtonMail Secure Email.</p>
<p dir="ltr">‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐<br>
On Thursday, April 2, 2020 2:26 PM, Liam Moncur <liam@moncur.me.uk> wrote:</p>
<p dir="ltr">> Hey,<br>
> I am seeing an issue where nginx seems to get stuck in a loop soon after the above error. From the debug I am seeing:<br>
><br>
> 2020/04/02 14:09:10 [error] 12875#12875: *338 SSL_read() failed (SSL: error:1409441A:SSL routines:ssl3_read_bytes:tlsv1 alert decode error:SSL alert number 50) while reading response header from upstream, client: 2a00:23c6:8238:6501:54e9:28f4:54e:1a91, server: <a href="http://www.findafishingboat.com">www.findafishingboat.com</a>, request: "GET /boat-list/fishing-boats-for-sale-over-15m HTTP/2.0", upstream: "<a href="https://194.39.167.98:443/boat-list/fishing-boats-for-sale-over-15m">https://194.39.167.98:443/boat-list/fishing-boats-for-sale-over-15m</a>", host: "<a href="http://www.findafishingboat.com">www.findafishingboat.com</a>"<br>
><br>
> Then shortly after I get a loop of the following:<br>
><br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http write filter 0000000000000000<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http copy filter: -2 "/boat-list/fishing-boats-for-sale-over-15m?"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http output filter "/boat-list/fishing-boats-for-sale-over-15m?"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http copy filter: "/boat-list/fishing-boats-for-sale-over-15m?"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 lua capture body filter, uri "/boat-list/fishing-boats-for-sale-over-15m"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http postpone filter "/boat-list/fishing-boats-for-sale-over-15m?" 0000000000000000<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http write filter: l:0 f:0 s:0<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http write filter limit 0<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http write filter 0000000000000000<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http copy filter: -2 "/boat-list/fishing-boats-for-sale-over-15m?"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http output filter "/boat-list/fishing-boats-for-sale-over-15m?"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http copy filter: "/boat-list/fishing-boats-for-sale-over-15m?"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 lua capture body filter, uri "/boat-list/fishing-boats-for-sale-over-15m"<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http postpone filter "/boat-list/fishing-boats-for-sale-over-15m?" 0000000000000000<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http write filter: l:0 f:0 s:0<br>
> 2020/04/02 14:09:10 [debug] 12875#12875: *338 http write filter limit 0<br>
><br>
> Any thoughts would be lovely.<br>
><br>
> Thanks,<br>
> Liam</p>
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