It is the number of possible paths from an LPAR through connections and directors to the device. If you have 4 CHIPIDs assigned to an LPAR to a Director, then 8 connections to a second Director then 8 connections to a DASD unit you have 4 * 8 * 8 paths and you are at your 256 path limit.
The LPAR could use any of the the CHIPIDs for an IO, the first director could use any of the 8 connections to the second director, and the second director could use any of the 8 connections to the DASD. On Thu, Jan 2, 2014 at 4:43 AM, R.S. <r.skoru...@bremultibank.com.pl> wrote: > ??? > Could you explain the limitation? > Do you mean limit of logical paths per chpid? Caution: it depends on the > controller, different limits can be in case of HDS Lightning and EMC DMX. > Regarding switches - this is first time I heard the use of switches change > the limit. > > In simple scenario, # of logical paths is # of LPARs attached to the CU port > (in the DASD box, not in CPC) x # of LCUs: > #LPs=#LPARs x #LCUs > > Note: when using switches it is possible to attach more CPCs (and maybe more > LPARs) to the CU port. > > > > -- > Radoslaw Skorupka > Lodz, Poland > > > > > > > > W dniu 2014-01-02 01:19, Mike Schwab pisze: >> >> The total number of paths must be kept at 256 or less. >> With 2 cascading directors: >> (LPAR <-> CNTRL1) * (CNTRL1 <-> CNTRL2) * (CNTRL2 -> DASD). >> 4 * 8 * 8 would be 256. >> With a single director 16 * 16 is possible but not usually needed. >> >> >> On Tue, Dec 31, 2013 at 8:26 AM, Dazzo, Matt <mda...@pch.com> wrote: >>> >>> We have a new IBM DS8870 that I have to define to the IODF. We are going >>> to have (16) 2107 type LCU's controllers and about 3k total devices defined >>> to those 16 LCU's. We also have 16 FICON channels available to use, I was >>> thinking about defining 8 channels to each LCU. >>> >>> We currently have 4 channels defined to each LCU on our existing Shark >>> device. We do not experience any IO delays or contention with this config. >>> >>> My experience in this area as you can tell is a little limited. As far as >>> channels are concerned is the motto 'the more the merrier' apply here? Or >>> should I follow the existing standard of 4 channels to each LCU? Any >>> standard to follow? >>> >>> Thanks Matt >>> >>> ---------------------------------------------------------------------- >>> For IBM-MAIN subscribe / signoff / archive access instructions, >>> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN >> >> >> > > > > -- > Tre tej wiadomo ci mo e zawiera informacje prawnie chronione Banku > przeznaczone wy cznie do u ytku s u bowego adresata. Odbiorc mo e by > jedynie jej adresat z wy czeniem dost pu osób trzecich. Je eli nie jeste > adresatem niniejszej wiadomo ci lub pracownikiem upowa nionym do jej > przekazania adresatowi, informujemy, e jej rozpowszechnianie, kopiowanie, > rozprowadzanie lub inne dzia anie o podobnym charakterze jest prawnie > zabronione i mo e by karalne. Je eli otrzyma e t wiadomo omy kowo, > prosimy niezw ocznie zawiadomi nadawc wysy aj c odpowied oraz trwale usun > t wiadomo w czaj c w to wszelkie jej kopie wydrukowane lub zapisane na > dysku. > > This e-mail may contain legally privileged information of the Bank and is > intended solely for business use of the addressee. This e-mail may only be > received by the addressee and may not be disclosed to any third parties. If > you are not the intended addressee of this e-mail or the employee authorized > to forward it to the addressee, be advised that any dissemination, copying, > distribution or any other similar activity is legally prohibited and may be > punishable. If you received this e-mail by mistake please advise the sender > immediately by using the reply facility in your e-mail software and delete > permanently this e-mail including any copies of it either printed or saved > to hard drive. > > mBank S.A. z siedzib w Warszawie, ul. Senatorska 18, 00-950 Warszawa, > www.mBank.pl, e-mail: kont...@mbank.pl S d Rejonowy dla m. st. Warszawy XII > Wydzia Gospodarczy Krajowego Rejestru S dowego, nr rejestru przedsi biorców > KRS 0000025237, NIP: 526-021-50-88. Wed ug stanu na dzie 01.01.2013 r. > kapita zak adowy mBanku S.A. (w ca o ci wp acony) wynosi 168.555.904 z ote. > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
