Hi, On the same question, is it possible to write a looping script to periodically rescan/reconnect invoking iscsiadm?
Thanks! - Kun On Mon, Mar 29, 2010 at 11:03 AM, Mike Christie <micha...@cs.wisc.edu> wrote: > On 03/28/2010 03:28 AM, Raimund Sacherer wrote: >> >> I am new to iSCSI and FilerSystems, but I am evaluating if it makes sense >> for our clients. >> >> So I set up my testlab and created a KVM Server with 3 instances, >> >> 2 x Ubuntu (one for Zimbra LDAP, one for Zimbra Mailserver) >> 1 x Ubuntu (with some OpenVZ virtual machines in it) >> >> These 3 KVM instances have RAW LVM disks which are on a Volume in the >> iSCSI Filer. >> >> I tried yesterday to reboot the filer, without doing anything to the KVM >> Machines, to simulate outage/human error. >> >> The reboot is fine and the iSCSI targets get exposed, but the KVM Servers >> have their filesystems mounted readonly. >> > > In this type of setup you will want high noop values (or maybe just turn > them off) and a high replacement_timeout value. So in the iscsid.conf for > the iniatitors do something like: > > # When the iscsi layer detects it cannot reach the target, it will stop IO > and if it cannot reconnect to the target within the timeout below it will > fail IO. This will cause FSs to be remounted read only or for you to get IO > errors. So set this to some value that is long enough to handle your > failure. > node.session.timeo.replacement_timeout = 600 > > # you can just turn these off > node.conn[0].timeo.logout_timeout = 0 > node.conn[0].timeo.noop_out_interval = 0 > > > Some else said to use dm-multipath and for that you could set the > queue_if_no_path to 1 or set no_path_retry to a high value. This will > basically just catch the iscsi/scsi layer and add extra requeuing > capabilities. queue_if_no_path will internally queue IO until the path comes > back or until the system runs out of memory or dies in some other way. > > -- > You received this message because you are subscribed to the Google Groups > "open-iscsi" group. > To post to this group, send email to open-is...@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. > > -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to open-is...@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.
