RE: Informix and firewalls
On a machine that speaks on an IP network, there are 65535 (2**16 - 1) ports that can make connections. There are a number of types of IP packets that can use each port: TCP, UDP, ICMP (are there more?). A firewall is a program that plugs all these ports and then selectively opens ports for use by programs running on the machine. Configuration-wise, your firewall is probably a ruleset, with "don't allow anything to pass" as the final rule, e.g.: allow tcp from 122.29.111.0/24 325 to 133.133.133.133 330 via 133.133.133. 133 allow udp from 222.123.123.123 to 133.133.133.133 230 via 133.133.133.133 deny any from all to all In this example, the firewall machine has IP address 133.133.133.133. There are only two kinds of packets allowed into the machine: (1) TCP packets coming from the 122.29.111.0/24 network from port 325 that are sent to port 33 on the firewall machine, with the packets entering through interface 133. 133.133.133; (2) UDP packets coming from IP address 222.123.123.123 (any port) that are sent to port 230 on the firewall machine, with the packets entering through interface 133.133.133.133. The final rule is not to allow anything else through the firewall. That's what a basic firewall does. -------------------------------------------------------- Peeter Pirn http://www.lfg.com > -----Original Message----- > From: Simbarashe.Pangeti@icl.com@internet > [mailto:Simbarashe.Pangeti@icl.com] > Sent: Tuesday, October 10, 2000 1:24 AM > To: informix-list@iiug.org@internet > Subject: Informix and firewalls > > > well i want to query an Informix database from the internet > and I do need to > secure it before > I do any thing so I have seen something about fire walls and > I need help on > this one > what are fire walls ? > how can I use them given perl,cgi,informix and a Unix server? > How can I implement them? > > -----Original Message----- > From: Astemborski, Jon [mailto:JAstemborski@biztravel.com] > Sent: Monday, October 02, 2000 3:27 PM > To: 'informix-list@iiug.org' > Subject: > > > Hello everyone, > > I am trying to update a table based on the contents of > another table but > only where the primary keys are equal. Because I can not > directly reference > the non updated table in a from statement it throws off what > I want to do. > I tried to replicate it with a sub queries but I received > error 284 (a query > has not returned not exactly one row). I understand the > error, but how can > I perform a multirow update based on the contents of another table? > > (I have tried numerous other variations but to no avail) > > update bizguaranteereq > set (occurdate,itineraryid,statuscd,moddate) = > ((select a1.creationdate,a1.itineraryid, > 99 statuscd, today moddate > from incentval a1, biztemp a2 > where a1.userid=a2.userid and a1.offercode=a2.servissue > and statuscd!=99)) where userid=(select userid from incentval) > and servissue=(select offercode from incentval > > Regards, > Jon Astemborski >