<4>Jul 28 17:11:53 hq-data001 kernel: [19076.667720] [UFW BLOCK] IN=ens5 OUT= MAC=02:87:42:3e:4f:ba:02:4b:94:bf:cd:44:08:00 SRC=80.51.182.101 DST=83.255.121.87 LEN=52 TOS=0x00 PREC=0x00 TTL=254 ID=63916 DF PROTO=TCP SPT=2049 DPT=880 WINDOW=1502 RES=0x00 ACK URGP=0 
This is a syslog message from a product called Uncomplicated Firewall (UFW) by linux. The following fields were extracted from the message:
action: block
clientport: 2049
facilitylabel: kernel
localhostname: hq-data001
localstarttime: Jul 28 17:11:53
messagetype: firewall_action
priority: 4
program: kernel
protocol: 6
senderhost: 10.1.100.121
sensitivity: normal
serverbytes: 52
serverport: 880
severitycode: 4
severitylabel: warning
sourceinfo: unknown
tags: ['rfc3164', 'ufw', 'firewall_action']
streamName: ufw
clientIP: 80.51.182.101
serverIP: 83.255.121.87