ANd one more thing about Ping vs Tnsping when going thru a firewall. Some firewalls are setup to not allow a Ping to pass thru, but sql connections are allowed. So a Ping will return not found, while a tnsping will return ok. I have that situation here all over the freakin place.
Tom Mercadante Oracle Certified Professional -----Original Message----- Sent: Tuesday, December 23, 2003 5:54 AM To: Multiple recipients of list ORACLE-L I came across just this last week with one of our monitoring tools. We set up an execution of a script that was using PING to check whether the status of a list of remote POS devices to make sure they were available. The collection worked fine - until we shutdown the POS device, and physically switched it off - and the PING still replied! The POS devices have UPS built in to them.. The client also thought it may have been the way that DNS/DHCP was set up via the router. It stumped me for a time.. ;) We use NETSVC now to check for the status of a service. Mark =================================================== Mark Leith | T: +44 (0)1905 330 281 Sales & Marketing | F: +44 (0)870 127 5283 Cool Tools UK Ltd | E: [EMAIL PROTECTED] =================================================== http://www.cool-tools.co.uk Maximising throughput & performance -----Original Message----- Jared Still Sent: 23 December 2003 04:34 To: Multiple recipients of list ORACLE-L Paul mentioned a few reasons for this. Another is that a ping does not get past the NIC. The ping is answered by software running on the card. You may have noticed at times that a ping is not a reliable method for determining if a server is still functioning. The OS can crash, but the NIC still responds to a ping. Tnsping on the other hand must get a response from Oracle Net service or daemon running on the server, a much longer path as Paul pointed out. HTH Jared On Mon, 2003-12-22 at 17:29, Murali Vallath wrote: > I have recently noticed in this one situation that there is a great difference between a tnsping vs a regular ping to the same server. > > for example this tnsping took about 270 ms which is strange and its consistent > > Used TNSNAMES adapter to resolve the alias > Attempting to contact (DESCRIPTION = (ADD > RESS_LIST = (load_balance = on) (failover = on) (ADDRESS = (PROTOCOL = TCP)(HOST > = myhost1.com)(PORT = 1521)) (ADDRESS = (PROTOCOL = TCP)(HOST = myhost2.com)( > PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = xyzdb) (FAILOVER_MODE = (TYPE > = SELECT) (METHOD = BASIC) (RETRIES = 20) (DELAY = 15)))) > OK (270 msec) > > and a ping to the same host > > Ping statistics for x.x.x.x: > Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), > Approximate round trip times in milli-seconds: > Minimum = 61ms, Maximum = 70ms, Average = 67ms > > Why could there be such a difference? > > > > > > > > --------------------------------- > Do you Yahoo!? > Yahoo! Photos - Get your photo on the big screen in Times Square -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Jared Still INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.553 / Virus Database: 345 - Release Date: 18/12/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.553 / Virus Database: 345 - Release Date: 18/12/2003 -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Mark Leith INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Mercadante, Thomas F INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).