This is a generic syslog content pack for Graylog with following extractor
SSH_login_username (Regular expression)
SSH_login_username_publickey (Regular expression)
SSH_fail_source (Regular expression)
SSH_fail_username (Regular expression)
Generic_IP_Extractor (Regular expression)
Generic_IP_Extractor (Regular expression)
SSH_fail_invalid_username (Regular expression)
IPTables_Packet_Dropped_iptables_dst (Regular expression)
IPTables_Packet_Dropped_iptables_src (Regular expression)
IPTables_Packet_Dropped_iptables_dport (Regular expression)