Mike, Thanks for your prompt/detailed reply.
Vtrak is an iscsi disk array, which unfortunately doesn't seem to be reporting any errors. Is there any sort of debugging I could do to discern what the cause of the problem is? I'm pretty sure it's not a pulled cable, but either the target or the initiator dropping the connection for some reason... What sort of "invalid data" would cause the initiator to drop the connection? There are no errors about pings or nops. The fragment I sent was the "beginning" of the problem. Can the verbosity of the iscsi messages be increased? Below is the output of iscsiadm -m session -P 3. The connection failed again over the weekend, this time I wasn't even doing any reads/writes. Some different error messages in there too, though I've seen these before. Sep 27 02:51:04 spin kernel: connection4:0: iscsi: detected conn error (1011) Sep 27 02:51:05 spin iscsid: Kernel reported iSCSI connection 4:0 error (1011) s tate (3) Sep 27 02:51:08 spin iscsid: connect to 188.8.131.52:3260 failed (Connection r efused) Sep 27 02:51:41 spin last message repeated 9 times Sep 27 02:52:45 spin last message repeated 17 times Sep 27 02:53:49 spin last message repeated 17 times Sep 27 02:54:52 spin last message repeated 17 times Sep 27 02:55:56 spin last message repeated 17 times Sep 27 02:56:00 spin iscsid: connect to 184.108.40.206:3260 failed (Connection r efused) Sep 27 02:56:04 spin kernel: session4: iscsi: session recovery timed out after 300 secs Sep 27 02:56:04 spin iscsid: connect to 220.127.116.11:3260 failed (Connection r efused) ... Sep 27 04:02:33 spin last message repeated 7 times Sep 27 04:02:35 spin kernel: iscsi: cmd 0x28 is not queued (8) Sep 27 04:02:35 spin kernel: sd 8:0:0:0: SCSI error: return code = 0x00010000 Sep 27 04:02:35 spin kernel: end_request: I/O error, dev sde, sector 549316386 Sep 27 04:02:35 spin kernel: I/O error in filesystem ("sde1") meta-data dev sde1 block 0x20bde700 ("xfs_trans_read_buf") error 5 buf count 8192 Sep 27 04:02:37 spin iscsid: connect to 18.104.22.168:3260 failed (Connection r efused) Sep 27 04:02:39 spin kernel: iscsi: cmd 0x28 is not queued (8) Sep 27 04:02:39 spin kernel: sd 8:0:0:0: SCSI error: return code = 0x00010000 Sep 27 04:02:39 spin kernel: end_request: I/O error, dev sde, sector 446314 Sep 27 04:02:39 spin kernel: I/O error in filesystem ("sde1") meta-data dev sde1 block 0x6cf48 ("xfs_trans_read_buf") error 5 buf count 4096 ... iSCSI Transport Class version 2.0-724 version 2.0-871 Target: reserve.vtrak Current Portal: 22.214.171.124:3260,1 Persistent Portal: 126.96.36.199:3260,1 ********** Interface: ********** Iface Name: default Iface Transport: tcp Iface Initiatorname: unknown Iface IPaddress: 188.8.131.52 Iface HWaddress: default Iface Netdev: default SID: 4 iSCSI Connection State: TRANSPORT WAIT iSCSI Session State: Unknown Internal iscsid Session State: REOPEN ************************ Negotiated iSCSI params: ************************ HeaderDigest: None DataDigest: None MaxRecvDataSegmentLength: 131072 MaxXmitDataSegmentLength: 524288 FirstBurstLength: 131072 MaxBurstLength: 262144 ImmediateData: Yes InitialR2T: Yes MaxOutstandingR2T: 1 ************************ Attached SCSI devices: ************************ Host Number: 8 State: running scsi8 Channel 00 Id 0 Lun: 0 Attached scsi disk sde State: running -----Original Message----- From: Mike Christie [mailto:micha...@cs.wisc.edu] Sent: Friday, September 25, 2009 8:46 PM To: firstname.lastname@example.org Cc: Drew Morris Subject: Re: connection error kills iscsi session djmorris wrote: > Problem: While running a backup to a mounted iscsi device, iscsid gets > a "conn error (1011)", and my drive starts getting input/output > errors. > > Details: > Kernel Version: 184.108.40.206-88.fc7PAE > Distribution: Fedora core 7 > open-iscsi version: 2.0-871 > > ISCSI Target Device: Promise Vtrak M610i > backup program: BackupPC (uses rsync) > my linux box and target are both plugged into a Netgear 516T Switch > (1000 baseT, 16 port, unmanaged) > > When I log into the target after this happens, i notice that there are > no active iscsi sessions > However, when i run > iscsiadm -m session, it lists the active session > > tcp:  TAR.GET.IP.ADR:3260,1 reserve.vtrak > > I can log out with > iscsiadm -m node -U manual > but i cannot log in after that or even discover the target device > unless i reboot that device > > sample from my /var/log/messages: > Aug 22 23:56:02 bold kernel: connection12:0: detected conn error > (1011) Is there anything before this? About a nop or ping maybe? > Aug 22 23:56:03 bold iscsid: Kernel reported iSCSI connection 12:0 > error (1011) > state (3) > Aug 22 23:56:06 bold iscsid: connect to 220.127.116.11:3260 failed > (Connection r > efused) > Aug 22 23:56:39 bold last message repeated 9 times > Aug 22 23:57:43 bold last message repeated 17 times > Aug 22 23:58:43 bold last message repeated 16 times > Aug 22 23:58:47 bold iscsid: > Aug 22 23:58:47 bold iscsid: connect to 18.104.22.168:3260 failed > (Connection r > efused) > Aug 22 23:59:21 bold last message repeated 9 times > Aug 23 00:00:24 bold last message repeated 17 times > Aug 23 00:01:02 bold last message repeated 10 times > Aug 23 00:01:02 bold kernel: session12: session recovery timed out > after 300 se We can get a conn error (1011) for any old reason. It is a generic error value (1011 == connection error). The target could have died, or someone could have pulled a cable or the target could have dropped the session/connection for some reasons, or we the target could have sent us some invalid data. When you see that message, it means the initiator is going to drop the tcp/ip and iscsi connection if it is not already gone then try to create a new tcp connection and relogin. The connect to 22.214.171.124:3260 failed (Connection refused) means that when we tried to reconnect, the target did not allow the connection. We do not have any more info than that. You should check the target logs. Maybe there was some resource issue or maybe it got rebooted. I have no idea. The recovery timed out after 300 secs message means we tried to reconnect for 300 secs but we could not. At this time, the iscsi initiator will just fail IO and you get the FS errors. However, it will continue to try and reconnect to the target (this is more useful for multipath). iscsiadm -m session will show the iscsi sessions that we are logged in to and sessions that were connected and we are trying to log back into. This is why it will show sessions where the target may only show targets that are logged in (I have not idea what vtrak does). If you run iscsiadm -m session -P 3 It will tell if the state of the session. No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.409 / Virus Database: 270.13.112/2394 - Release Date: 09/25/09 17:52:00 This e-mail may contain confidential, personal and/or health information(information which may be subject to legal restrictions on use, retention and/or disclosure) for the sole use of the intended recipient. Any review or distribution by anyone other than the person for whom it was originally intended is strictly prohibited. If you have received this e-mail in error, please contact the sender and delete all copies. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to email@example.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 -~----------~----~----~----~------~----~------~--~---