Maybe the approach you end up taking will be dictated by the reason why you have to switch to SSL in the first place. If it's being done to meet specific audit requirements "security by obscurity" won't do it. You may be able to meet standards by starting a second IP stack minus SSL only in an emergency (and only long enough to correct the issue with the stack that's SSL-enabled.)
-----Original Message----- From: The IBM z/VM Operating System To: IBMVM@LISTSERV.UARK.EDU Sent: 4/16/2008 6:27 PM Subject: Second TCPIP stack and SSL We have been ordered to protect all TN3270 sessions to VM with SSL. This means turning on SSLSERV and disabling non-SSL. (INTERNALCLIENTPARMS SECURECONNECTION REQUIRED, I think.) IBM level 2 has suggested that other shops have a second TCP/IP stack to use when there are problems with TCPIP or SSLSERV. (We have found several problems with SSLSERV in our testing.) I'm curious whether and how other shops use a second TCP/IP stack. Some possibilities: 1. Have a second TCPIP stack up all the time (userids TCPIP2 and MPROUTE2), but with no SSL. It would run on a second IP address. (This is security by obscurity.) 2. Have a second TCPIP stack up all the time, with SSL required. (Userids TCPIP2, MPROUTE2, SSLSERV2.) This takes 2-3 more 3390-3 packs per system, as well as a second IP address for each. (We have 6 first-level VM systems, so those packs add up. There is also the administrative time to get new certificates, etc.) 3. Have a second TCPIP stack, kept down, with no SSL, but brought up by operations when we request it. It would have a second IP address. (So we could test without bringing down the other TCPIP stack.) 4. Have a second TCPIP stack, kept down, with no SSL, but brought up by operations when we request it. Assume the first stack is down and steal the IP address. We could only test during stand-alone time. We do have a seond way to get into our systems, a PC-based product called AP View. It has been unreliable here, and in some cases we have to ask operations to page the AP View support, either becsaue it is not working or because we are only allowed Read/Only access via AP View to some (the most important, naturally) VM systems. This slows down recovery. We are trying to get rid of VTAM. (Actually, we are waiting for the z/OS folks on this.) So that is not a good alternative. Alan Ackerman Alan (dot) Ackerman (at) Bank of America (dot) com
