Yep, exactly, you need two newlines (2 times 0x0d0a) to generate a completely empty line, which HTTP uses to signal that the header section is over.
On Tue, Feb 2, 2021 at 3:35 PM Christopher Parsons <[email protected]> wrote: > It appears there's just a single CRLF (0d 0a) after the 200 OK line. Are > you saying there needs to be another one in order for AlertManager to > detect a valid 200 response? > > [image: mon101 response with hex.PNG] > > On Tuesday, February 2, 2021 at 4:25:13 AM UTC-5 [email protected] > wrote: > >> Hi Christopher, >> >> It's not clear from your Wireshark stream, maybe show the data as hex >> instead: does the problematic server insert an empty line after the >> "HTTP/1.1 200 OK" line and then terminate the connection? So a CRLF after >> the 200 line and another CRLF for the empty line. This is required for the >> response to be read as a valid HTTP response (the body is optional). >> >> Julius >> >> On Tue, Feb 2, 2021 at 12:45 AM Christopher Parsons <[email protected]> >> wrote: >> >>> Hello, >>> >>> I have a third party tool that is listening for incoming HTTP messages >>> on a specific port. When we point AlertManager to this endpoint, >>> notifications are delivered and consumed by the third party tool and >>> inserted into our monitoring database successfully. However, AlertManager >>> continuously retries the notification and slowly backs off on the retries. >>> >>> In order to try to figure out what's going on, we set up packet captures >>> on AlertManager server and one on the endpoint server. As a control group, >>> we also configured a simple node.js server which responds back with a 200. >>> The only difference, as far as I can tell, from the TCP streams in >>> Wireshark is the response headers. The server forcing AlertManager to >>> continuously retry replies with a simple "*HTTP/1.1 200 OK*". However, >>> the node.js control group which does not force AlertManager to send >>> subsequent replies is responding with something like... >>> >>> *HTTP/1.1 200 OK* >>> >>> *Date: Mon, 01 Feb 2021 22:56:09 GMT* >>> >>> *Connection: keep-alive* >>> >>> *Transfer-Encoding: chunked* >>> >>> Does the go-lang web server expect more than a simple "HTTP/1.1 200 OK" >>> as a response? The third party tool is not open source but I may be able >>> to get them to issue a future update if this is considered unexpected >>> behavior. Any suggestions or workarounds would be greatly appreciated. >>> I've also attached a couple of screenshots from the Wireshark TCP stream >>> traces for reference. >>> >>> Normal behavior: >>> >>> [image: logserver normal behavior.PNG] >>> >>> Repeat notification behavior: >>> [image: mon101 repeat behavior.PNG] >>> >>> Please let me know if there are any other details I can provide! >>> >>> Thanks, >>> Chris >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Prometheus Users" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/prometheus-users/014b62ad-72bb-41af-b794-f3bbe61bf705n%40googlegroups.com >>> <https://groups.google.com/d/msgid/prometheus-users/014b62ad-72bb-41af-b794-f3bbe61bf705n%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> >> >> -- >> Julius Volz >> PromLabs - promlabs.com >> > -- > You received this message because you are subscribed to the Google Groups > "Prometheus Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/prometheus-users/83566c90-0119-4e7d-97fb-23d30c21299cn%40googlegroups.com > <https://groups.google.com/d/msgid/prometheus-users/83566c90-0119-4e7d-97fb-23d30c21299cn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- Julius Volz PromLabs - promlabs.com -- You received this message because you are subscribed to the Google Groups "Prometheus Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/prometheus-users/CAObpH5zZAfZzB_TwTrPqAo%3DtVDBe8w%3DgfJN%2BbyhoucpiUf%3DuUQ%40mail.gmail.com.
