Parse one line as two lines

[Sjap1 (Søren Andersen)]

Hello,

I'm trying to parse multiple items in one line. My grok pattens match but logstash are outputting the data as arrays; How can i make the output look the where are two lines?

input data:

2021-11-01 14:09:34 CET Address: 2a03:1234:1234:4::142 has been assigned for 7257600 seconds to a device with DUID: 00:03:00:01:00:1e:80:ec:8a:f4 connected via relay at address: fe80::21e:80ff:feec:8af4 for client on link address: 2a03:1234:1234:4::1, connected at location interface-id: 61:65:33:32:30:3a:32:36:36:39:2d:34Prefix: 2a03:1234:1234:1900::/56 has been assigned for 7257600 seconds to a device with DUID: 00:03:00:01:00:1e:80:ec:8a:f4 connected via relay at address: fe80::21e:80ff:feec:8af4 for client on link address: 2a03:1234:1234:4::1, connected at location interface-id: 61:65:33:32:30:3a:32:36:36:39:2d:34

I've created two grok patterns to match the input:

%{TIMESTAMP_ISO8601:time} .* Address: .* has been .* for .* seconds to a device with DUID: .* connected via relay at address: .* for client on link address: .* connected at location interface-id: .*Prefix: %{GREEDYDATA:client_ip} has been %{WORD:action} for %{INT:leasetime} seconds to a device with DUID: .* connected via relay at address: .* for client on link address: .* connected at location interface-id: (?<interfaceid>[0-9a-f]{2}(:[0-9a-f]{2})*)
%{TIMESTAMP_ISO8601:time} .* Address: %{GREEDYDATA:client_ip} has been %{WORD:action} for %{INT:leasetime} seconds to a device with DUID: .* connected via relay at address: .* for client on link address: .* connected at location interface-id: (?<interfaceid>[0-9a-f]{2}(:[0-9a-f]{2})*)

My issue is the output is an array:

{
      "client_ip" => [
        [0] "2a03:1234:1234:4::142 has been assigned for 7257600 seconds to a device with DUID: 00:03:00:01:00:1e:80:ec:8a:f4 connected via relay at address: fe80::21e:80ff:feec:8af4 for client on link address: 2a03:1234:1234:4::1, connected at location interface-id: 61:65:33:32:30:3a:32:36:36:39:2d:34Prefix: 2a03:1234:1234:1900::/56",
        [1] "2a03:1234:1234:1900::/56"
    ],

[AquaX (Andreas Helmer)]

I'm not sure why it is splitting it into an array.. there may be an invisible newline character. However, you can cheat a little bit and ensure that client_ip is flattened out by using the mutate join filter.

   filter {
     mutate {
       join => { "client_ip" => " " }
     }
   }

Mutate filter plugin | Logstash Reference [7.15] | Elastic