To avoid timeout errors, IBM recommends having no more then 32 servers per an NPIV-mode FCP channel. The 480 servers is ok on non-NPIV FCP.
(see "Introducing N_Port Identifier Virtualization for IBM System z9" page 4 http://www.redbooks.ibm.com/redpapers/pdfs/redp4125.pdf ) " Configuration considerations Some general recommendations for using NPIV include: Do not use more than 32 subchannels per physical channel in NPIV mode. Also, do not perform more than 128 total target logins (for example, in a configuration with 32 subchannels, limit the number of target logins to no more than an average of 4). Using more subchannels, target logins, or both can create timeouts." -------------------------------------------------------- This e-mail, including any attachments, may be confidential, privileged or otherwise legally protected. It is intended only for the addressee. If you received this e-mail in error or from someone who was not authorized to send it to you, do not disseminate, copy or otherwise use this e-mail or its attachments. Please notify the sender immediately by reply e-mail and delete the e-mail from your system. -----Original Message----- From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of Alan Altmark Sent: Friday, December 07, 2007 11:25 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: SAN and Linux on zSeries On Friday, 12/07/2007 at 06:16 EST, Rick Troth <[EMAIL PROTECTED]> wrote: > Handing each guest its own HBA (host bus adapter, > the open systems term for and FCP adapter) kind of blows > one of the reasons to go virtual. Eh? 480 servers can use a single FCP adapter (chpid) concurrently. That's the whole point of N_port ID virtualization: 480 separate fabric endpoints. Alan Altmark z/VM Development IBM Endicott
