2 Problemi di aggiornamento relativi all'escaping

Superato il limite di caratteri per i parametri delle funzioni dopo l'aggiornamento

In Zabbix 7.0 è stato aggiunto l'escaping corretto delle barre rovesciate nei parametri stringa delle funzioni dello storico.

Poiché durante l'aggiornamento dalle versioni di Zabbix precedenti alla 7.0 vengono aggiunte barre rovesciate supplementari, i parametri diventano più lunghi e questo può causare il malfunzionamento delle funzioni dei trigger se la lunghezza del parametro supera la dimensione massima dei dati di 255 caratteri.

Per illustrare quali problemi possono sorgere durante l'aggiornamento del database, quale sia il loro impatto e come riconoscerli e risolverli, prendiamo come esempio una configurazione con 3 item e 2 trigger.

Configurazione

1. Versione Zabbix 6.0.

2. File /tmp/ONE che contiene 114 barre rovesciate con una 'a' alla fine:

\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a

3. Un item vfs.file.contents[/tmp/ONE] per leggere /tmp/ONE.

4. Due item calcolati:

Calc_228 - il suo parametro contiene 228 barre rovesciate nel parametro, che sono precedute da escape, quindi corrispondono alle 114 barre rovesciate del file /tmp/ONE:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a")

Calc_232 - il suo parametro contiene 232 barre rovesciate nel parametro, che sono precedute da escape, quindi non corrispondono alle 114 barre rovesciate del file /tmp/ONE, poiché richiedono almeno 116 barre rovesciate reali:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a")

5. Due trigger:

Trig_228 - analogamente a Calc_228, il suo parametro contiene 228 barre rovesciate per corrispondere a 114 barre rovesciate reali del file /tmp/ONE:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a")

Trig_232 - analogamente a Calc_232, il suo parametro contiene 232 barre rovesciate per corrispondere a 116 barre rovesciate reali, quindi non corrisponde alle 114 barre rovesciate del file /tmp/ONE:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1h:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a")

6. Calc_228 restituisce 1 e Trig_228 si attiva.

7. Calc_232 restituisce 0 e Trig_232 non si attiva.

Aggiornamento

1. Eseguire l'aggiornamento alla versione 7.4.0, controllare i log per l'avviso:

2485502:20250228:115442.236 DBpatch_6050165(): cannot save in DB function parameter: resulting size 477 is longer than the maximum 255.
functionid:33792 function:'find'
used on host: 'Zabbix server'
  in trigger: 'TRIG_228'.
Current parameter value:
'$,1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a"'
Resulting escaped value would be:
'$,1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a"
DB upgrade and Zabbix server can continue to run, but to make sure this function works correctly
MANUAL INTERVENTION IS REQUIRED !
Need to manually reduce the size of this parameter with macro as a workaround.

2485502:20250228:115442.237 DBpatch_6050165(): cannot save in DB function parameter: resulting size 485 is longer than the maximum 255.
functionid:33795 function:'find'
used on host: 'Zabbix server'
  in trigger: 'TRIG_232'.
Current parameter value:
'$,1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a"'
Resulting escaped value would be:
'$,1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a"
DB upgrade and Zabbix server can continue to run, but to make sure this function works correctly
MANUAL INTERVENTION IS REQUIRED !
Need to manually reduce the size of this parameter with macro as a workaround.

2. L'aggiornamento del database si completa e Zabbix server continua a funzionare.

3. Calc_228 restituisce ancora 1 mentre Calc_232 restituisce 0.

4. I trigger sono stati aggiornati come segue:

Trig_228:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a")

Trig_232:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp","\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a")

Entrambi i trigger - Trig_228 e Trig_232 - si attivano ora! Questo è inaspettato, quindi è necessario un intervento manuale.

Intervento manuale

Le espressioni dei trigger devono essere aggiornate in modo che i backslash siano sottoposti a escape, tuttavia ciò non può essere fatto perché i parametri risultanti sarebbero troppo lunghi.

Per questo motivo è necessario aggiungere le macro:

{$228_BACKSLASHES_A}:

\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a

{$232_BACKSLASHES_A}:

\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\a

e aggiornare le espressioni dei trigger in modo che le utilizzino:

Trig_228:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp",{$228_BACKSLASHES_A})

Trig_232:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp",{$232_BACKSLASHES_A})

Ora entrambi i trigger funzionano come prima: solo Trig_228 si attiva.

Non ci sono problemi con gli item calcolati, ma anche questi potrebbero essere aggiornati per coerenza:

Calc_228:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp",{$228_BACKSLASHES_A})

Calc_232:

find(/Zabbix server/vfs.file.contents[/tmp/ONE],1m:now,"regexp",{$232_BACKSLASHES_A})