Shrey wrote: > Hi Mike, > > Thanks for you reply. Please find my reply inline. > > On May 19, 11:04 pm, Mike Christie <[EMAIL PROTECTED]> wrote: >> Shrey wrote: >>> Dear All, >>> I started using/studying open-iscsi recently. I was wondering if there >>> is any hard-coded limit to number of targets devices that can >>> discovered per iSCSI target? Is there any hard-coded limit on the >>> number of LUNs supported per target device (assuming that somehow HBA >>> on iscsi target doesn't present any limit) ? >> As others pointed out there is a module param for the max lun for >> iscsi_tcp, but that should actually be limited by a libiscsi/scsi-ml >> limit. libiscsi uses a function named int_to_scsilun in >> drivers/scsi/scsi_scan.c and as you can see that only implments 2 >> levels. libiscsi/iscsi_tcp also does not do the device scanning (the >> iscsi layer only finds the targets) so we are limited by scsi_scan.c. To >> get the limits for that do "modinfo scsi_mod". > > Ok, that gives me something to thing/experiment about. Thanks > >> There is also a limit on the number of targets. Because we allocate a >> scsi_host per session, and the scsi layer uses a unsigned short for the >> host number the number of targets is 2^16. > > That would mean 65536 devices. But I get stuck far below that - just > about 90 targets.
If you are using 869.* then the problem is most likely on the IET side. Like I said before I think you need to upgrade. I had the same problem when I was testing my fixes for lots of targets support. Oh yeah, I said this in some other mail, but will say it here so people can search for it. There is another target limit and that is the number of files a process can have open. We open a tcp socket for each session and we do a session to each target portal. We also will open other files so the exact number is not known. I think it is probably around 4000. I do not have a setup that supports that many targets yet to know exactly though. Let us know what you find out. > Are some parameters which I am missing which I need to configure or > take care of? > I tried tinkering "node.conn[0].iscsi.MaxRecvDataSegmentLength = > 65536" but there was no difference. This actually is making me think > that target is acting as a bottleneck. > That is just for normal sessions. You would want to set discovery.sendtargets.iscsi.MaxRecvDataSegmentLength but like I said that will not completely fix the problem. > I think I will post all this on the iscsi-target list. > > Thanks a lot > > -- > Shreyansh > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to open-iscsi@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/open-iscsi -~----------~----~----~----~------~----~------~--~---
