On Friday 14 September 2012 03:36 PM, Laszlo Fekete wrote: > > I have fresh debian squeeze with standard 2.6.32-5-amd64 kernel and > iscsitarget + iscsitarget-dkms packages and have some other squeeze > with open-iscsi initiators. > > The problem is after a long testing, that if there is more than 32 > active sessions when try /etc/init.d/iscsitarget restart, it sometimes > fails, so no more than 32 initiator can reconnect. >
What is the error you see on the initiator? Does it report that the connection already exists? > > > For more details: > > I have 16 targets with summary 40 active sessions, try to restart the > iscsi target and sometimes (not all the time, 20-60% of the tries for > me) it fail. first 32 clients can reconnect without problem, but the > others don't get answer from the target and don't working. There is no > error on target or initiator side, just the initiators try to reconnect. > > There is two type of the initiators: > > - using one session to access the target with only one ip, open-iscsi > config limits and timeout are the default > > - using 4 session to access the two target (some of the targets are > duplicated within 2 servers with drbd) with 2 session/ip per target. > These initiators using multipath and minimal (1sec) timeouts. > > Both type contains sessions which are just connected, but the target > isn't mounted on that client which failed to reconnect. > > > > If the iscsi target restart fail it random which initiator stuck, I > think it only depend on who is the faster to be in the first 32 session. > I am not sure here. The open-iscsi default replacement timeout is 120 secs. Even then, when the target is back, it will poll it. > Tried to check, maybe this is a network connection, but if the restart > fail and try to telnet to them sometimes it also don't answer (tcpdump > show, that the target server got the request, but don't send any answer). > > > > Checked that maybe on the iscsi target stop stucked, but it seems to > be okay, the session closed, the modules unloaded, there isn't any > error, tried to raise the sleep time before start to 10 sec from 1, > but got the same error. > What 1 sec setting are you referring here? > > > So I think there is a limit somewere that the in a short time no more > than 32 initiator can connect, but don't find any of this. > > Checked the newer iscsi targets changelog and don't see any report > that describe this problem, so don't tried to upgrade wheezy. > > > > Debian GNU/Linux 6.0, kernel 2.6.32-5-amd64, libc 2.11.3-3 > There are settings in ietd.conf where you can set the Max number of connections/sessions. Have you explored them? -- Ritesh Raj Sarraf | http://people.debian.org/~rrs Debian - The Universal Operating System
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