Hi dear dev team,<div><br></div><div>Is there a way to check if ODBC connection is alive and database is accessible from my module?</div><div><br></div><div>For example when I am executing the following in my code and database is down:</div>
<div><span class="Apple-style-span" style="font-family: arial, sans-serif; font-size: 13px; border-collapse: collapse; ">switch_odbc_handle_callback_exec(<b>globals.backup_odbc</b>, sql, my_func_callback, &pdata, NULL) != SWITCH_ODBC_SUCCESS</span></div>
<div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;"><br></span></font></div><div><span class="Apple-style-span" style="font-family: arial, sans-serif; border-collapse: collapse; ">it tries to reconnect 120 times to the database, before it gives up.</span></div>
<div><span class="Apple-style-span" style="font-family: arial, sans-serif; border-collapse: collapse; "><br></span></div><div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;">I have 2 options: </span></font></div>
<div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;">1. Check if the database is alive before executing this code (preferred)</span></font></div><div>
<font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;">2. Reduce max_tries to , say 3 from 120 (not preferred as it requires change in <span class="Apple-style-span" style="font-size: 13px; ">switch_odbc.c).</span></span></font></div>
<div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;"><br></span></font></div><div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;"><br>
</span></font></div><div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;">Could you please hint?</span></font></div><div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;"><br>
</span></font></div><div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;">Thank you,</span></font></div><div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;">Vitalie</span></font></div>
<div><font class="Apple-style-span" face="arial, sans-serif"><span class="Apple-style-span" style="border-collapse: collapse;"><br></span></font><br><div class="gmail_quote">2010/4/25 Vitalii Colosov <span dir="ltr"><<a href="mailto:vetali100@gmail.com">vetali100@gmail.com</a>></span><br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Hi,<div><br></div><div>I am using core ODBC for MySQL connect.</div><div><br></div><div>Trying to implement failover using 2 servers - main and backup.</div>
<div>If main server is not responding, it should try to query backup server.</div>
<div><br></div><div>The following is used in my module:</div><div><br></div><div><div>if (switch_odbc_handle_callback_exec(<b>globals.master_odbc</b>, sql, my_func_callback, &pdata, NULL) != SWITCH_ODBC_SUCCESS) {</div>
<div><span style="white-space:pre"> </span>switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "(***)Error running query on master database: [%s]\n", sql);</div><div><br></div><div><span style="white-space:pre"> </span>switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "(***)Trying backup database: [%s]\n", globals.backup_odbc);</div>
<div><br></div><div><br></div><div><span style="white-space:pre"> </span>if (switch_odbc_handle_callback_exec(<b>globals.backup_odbc</b>, sql, my_func_callback, &pdata, NULL) != SWITCH_ODBC_SUCCESS) {</div>
<div><span style="white-space:pre"> </span>switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "(***)Error running query on master and backup database: [%s]\n", sql);</div><div><span style="white-space:pre"> </span></div>
<div><span style="white-space:pre"> </span>} </div><div><span style="white-space:pre"> </span></div><div><span style="white-space:pre"> </span>}</div>
</div><div>...</div><div><br></div><div><br></div><div><br></div><div>Right now it tries to reconnect to main server 120 times before it gives up and goes to backup server.</div><div><br></div><div>I found the following in the switch_odbc.c:</div>
<div>int max_tries = 120;</div><div><br></div><div><br></div><div>Is there is a way to disable this check, so if it will not be able to connect to master, it will immediate go to backup server?</div><div>I know I can change the source, but this will be already "customized core" - don't want to go in this direction.</div>
<div><br></div><div><br></div><div>Or maybe there is a better way to handle database fail over in my module?</div><div><br></div><div><br></div><div>Thank you,</div><div>Vitalie</div>
</blockquote></div><br></div>