Re: Best way to create multiple TCP flows on 10 Gbps link
On Tue, 26 Aug 2014 13:05:11 -0700 Learner learner.st...@gmail.com wrote: How many iscsi and underlying top sessions are u using? If multiple, pls check if all to sessions are being used. Btw, what tuning did u perform to fix Tcp BDP issue? I'm just doing netcat tests to/from /dev/shm at the moment. I wouldn't consider it fixed necessarily, but the info from this link was useful: http://www.kehlet.cx/articles/99.html Thanks, Mark -- You received this message because you are subscribed to the Google Groups open-iscsi group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at http://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
Re: problems connecting to Equallogic 6100
iscsiadm -m node --login I have an EqualLogic and it works pretty well. I typically specify the target with -T, and the grapdmin user console shows errors too (if the initator is connect to a good IP). Is it timing out or failing right away? Can you double check that the target portal IP is correct? Maybe try defining the target as unrestricted to make sure it isn't a password kind of problem. Mark -- You received this message because you are subscribed to the Google Groups open-iscsi group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at http://groups.google.com/group/open-iscsi?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
Re: Multipath or not ?
I have a virtual tape library and a iscsi SAN. All have multiple ethernet interfaces, This will ressult in multiples sessions to the targets.So I wonder if I must use dm-multipath or not ? Does the Typically I only use multipath if I have one initiator talking to one target. Otherwise I just use 802.3ad/LACP and let the switch try to figure out the best way to route things. Mark -- You received this message because you are subscribed to the Google Groups open-iscsi group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at http://groups.google.com/group/open-iscsi?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
Re: Ubuntu server + open-iscsi + ocfs2. Connectivity loss causes immediate server reboot.
storage HP P2000 G3 iscsi. Even short network connectivity loss is causing immediate server crash and reboot. In syslog I can not found any Does ocfs2 have a fencing arrangement like Red Hat's gfs ? This is a feature actually, clustered filesystems don't want rogue machines writing straight to the block device. If this is the problem, there should be a way to tweak the timeouts. Red Hat's cluster system has an overwhelming amount of options available. FWIW, we gave up on Red Hat Cluster GFS, which is similar to OCFS, due to this type of outage. We switched to ASM and NFS. ASM works great with iscsi. Mark -- 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 open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
Re: General question on shared storage
AFAIK, Linux buffers blocks from block devices. So if host A reads a block from shared storage (e.g. the MBR), and later host B modifies that block, will host A still have the last block read in cache? If so there's a big problem. I am only familiar with GFS and ASM, and both of those will typically disable any sort of caching. Consider that you want to mount a non-clustered filesystem alternatingly on two hosts (like for a HA failover). If host A used the filesystem, the host B took over the filesystem without booting I would recommend only logging in from one host at a time. Some SAN types (e.g. EqualLogic) will allow multiple hosts to discover the target, but will only allow one to be logged in. This will help with split brain corruption issues. In general, though, you should be careful of trying to force a SAN type of solution when you really need NAS. NFS and Samba are quite mature and easy to deal with. Mark -- 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 open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
Re: Changes made on iSCSI disk are not shown on initiator
the mounted folder) I can see this file afterwards only on the initiator, but not on the target. Means, I open a Terminal on the The basic rule is that if you are going to export storage to a single machine, use iSCSI. If you need shared storage, use NFS instead. You could consider a shared storage file system like Oracle's ASM, but they aren't so easy to deal with. NFS4 has locking, user authentication, and everything you need built into the protocol. Mark -- 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 open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
Re: How to resurrect SCSI device
I'm facing a somewhat strange situation. As a part of testing a multipath solution, I've written a script that simulates the failure and This is an excellent thread, thanks. Does this happen even without multipathd? I have been trying to work on a procedure to fix a similar problem where the device is read-only even though the session was re-established - and there is no way to either unmount it or get it back to a state where it is usable. Mark -- 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 open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
Re: iscsiadm: discovery record not found
iscsiadm: Discovery record [$DP,3260] not found. It looks like you have a shell syntax problem here. DP should be the IP address (aka portal). Mark -- 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 open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
Re: iscsi and virtualization
This is apparently not a good idea - since, as far as I can tell at least, I have to restart the iscsi subsystem every time I present a new disk from the PS6000. A service iscsi restart effectively destroys all KVM guests using existing, already logged in iscsi disks will hang indefinitely wondering where their disks disappeared to. Ouch, you definitely don't want to do this. You should be able to just do a discovery and find new targets. The commands take some getting used to, though. Check out section 5.2 in this: http://www.open-iscsi.org/docs/README We have had pretty good luck with Equallogic RHEL5/CentOS 5. It would be a bit cleaner if there were a way to tell discovery of a particular target that you want to add, instead of doing a full scan, but it should be safe. Mark -- 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 open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
