## CS 591 K1: Data Stream Processing and Analytics Spring 2020 2/11: Windows and Triggers Vasiliki (Vasia) Kalavri vkalavri@bu.edu ## Window operators • Practical way to perform operations on unbounded have a start and an end timestamp. - All built-in window assigners provide a default trigger that triggers the evaluation of a window once the (processing or event) time passes the end of the window. • onTimer(timestamp: Long, ctx: OnTimerContext, out: Collector[OUT]) is invoked when a previously registered timer triggers. The timestamp argument gives the timestamp of the firing timer and the Collector allows emitting

86 5. Zabbix appliance 89 6. Configuration 93 1 Hosts and host groups 98 2 Items 106 3 Triggers 243 4 Events 258 5 Event correlation 260 6 Visualisation 265 7 Templates 307 8 Notifications Troubleshooting 893 2 Installation 894 3 Daemon configuration 897 4 Protocols 932 5 Items 946 6 Triggers 964 7 Macros 983 8 Setting time periods 995 9 Command execution ..... 995 10 Recipes for monitoring agents ## Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database ## Highly configurable alerting • sending notifications

RDB$RELATION_FIELDS 664 RDB$ROLES 666 RDB$SECURITY_CLASSES ..... 666 RDB$TRANSACTIONS ..... 666 RDB$TRIGGERS ..... 667 RDB$TRIGGER_TYPE Wert ..... 668 RDB$TRIGGER_MESSAGES ..... 671 RDB$TYPES ..... 671 einem Header und einem Body. Der Header gibt den Namen des Triggers, den Namen der Beziehung (bei einem DML-Trigger), die Phase des Triggers, die Ereignisse, auf die er angewendet wird, und die Position Deklarationen und eingebettete Anweisungen werden mit Semikolons (‘;’) abgeschlossen. Der Name des Triggers muss unter allen Triggernamen eindeutig sein. ## Statement-Terminatoren Einige SQL-Anweisungseditoren

appliance ..... 78 6. Configuration ..... 82 1 Hosts and host groups ..... 86 2 Items ..... 90 3 Triggers ..... 180 4 Events ..... 187 5 Visualisation ..... 188 6 Templates ..... 203 7 Notifications ..... 693 2 Installation ..... 694 3 Daemon configuration ..... 697 4 Items ..... 716 5 Triggers ..... 727 6 Macros ..... 743 7 Setting time periods ..... 780 8 Command execution ..... 780 agents ## Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database ## Highly configurable alerting • sending notifications

and trigger dependencies 128 10 User Parameters 128 11 Windows performance counters 130 12 Triggers 131 13 Screens and Slide Shows 142 14 IT Services 143 15 User permissions 146 16 The Queue **ERROR**, usually in Monitoring → Triggers section, when showing all hosts from all groups. This trigger can be deleted by clicking on it, choosing Configuration of triggers, then clicking on Delete in the Layout of this configuration has been redone in 1.8. Instead of separate sections for items, graphs, triggers and so on, they are folded into host configuration section, where convenient linking allows for

.... 93 6. Configuration ..... 97 1 Hosts and host groups ..... 102 2 Items ..... 107 3 Triggers ..... 225 4 Events ..... 234 5 Visualisation ..... 235 6 Templates ..... 253 7 Notifications Installation ..... 791 3 Daemon configuration ..... 794 4 Protocols ..... 819 5 Items ..... 820 6 Triggers ..... 833 7 Macros ..... 850 8 Setting time periods ..... 904 9 Command execution ..... 904 agents ## Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database ## Highly configurable alerting • sending notifications

Zabbix appliance 72 6. Configuration 78 1 Hosts and host groups ..... 83 2 Items ..... 89 3 Triggers ..... 207 4 Events ..... 215 5 Visualisation ..... 216 6 Templates ..... 246 7 Notifications ..... 782 2 Installation ..... 783 3 Daemon configuration ..... 786 4 Items ..... 814 5 Triggers ..... 827 6 Macros ..... 843 7 Setting time periods ..... 896 8 Command execution ..... 896 agents ## Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database ## Highly configurable alerting • sending notifications

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 3 Triggers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1271 6 Triggers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . agents Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database Highly configurable alerting • sending notifications

5. Zabbix appliance 115 6. Configuration 120 1 Hosts and host groups 125 2 Items 132 3 Triggers 266 4 Events 278 5 Visualisation 279 6 Templates 322 7 Notifications upon events 322 8 Installation ..... 965 3 Daemon configuration ..... 969 4 Protocols ..... 1003 5 Items ..... 1003 6 Triggers ..... 1023 7 Macros ..... 1045 8 Setting time periods ..... 1057 9 Command execution .... agents ## Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database ## Highly configurable alerting • sending notifications

... 98 7. Configuration ..... 102 1 Hosts and host groups ..... 107 2 Items ..... 115 3 Triggers ..... 269 4 Events ..... 285 5 Event correlation ..... 289 6 Visualisation ..... 294 7 Templates Troubleshooting 1002 2 Installation 1002 3 Daemon configuration 1008 4 Protocols 1044 5 Items 1060 6 Triggers 1084 7 Macros 1104 8 Unit symbols 1116 9 Setting time periods 1117 10 Command execution agents ## Flexible threshold definitions • you can define very flexible problem thresholds, called triggers, referencing values from the backend database ## Highly configurable alerting • sending notifications