From e16c816f97a865a709bbd2d8c01e7b1551b0cc97 Mon Sep 17 00:00:00 2001 From: Friedrich Weber Date: Fri, 11 Oct 2024 14:58:21 +0200 Subject: [PATCH] iscsi: disable Open-iSCSI login retries Since 90c1b10 ("fix #254: iscsi: add support for multipath targets"), iSCSI storage activation checks whether a session exists for each discovered portal. If there is a discovered portal without a session, it performs a discovery and login in the hope of establishing a session to the portal. If the portal is unreachable when trying to log in, Open-iSCSI's default behavior is to retry for up to 2 minutes, as explained in /etc/iscsi/iscid.conf: > # The default node.session.initial_login_retry_max is 8 and > # node.conn[0].timeo.login_timeout is 15 so we have: > # > # node.conn[0].timeo.login_timeout * \ > node.session.initial_login_retry_max = 120s If pvestatd is activating the storage, it will be blocked during that time, which is undesirable. This is particularly unfortunate if the target announces portals that the host permanently cannot reach. In that case, every pvestatd iteration will take 2 minutes. While it can be argued that such setups are misconfigured, it is still desirable to keep the fallout of that misconfiguration as low as possible. In order to reduce the time Open-iSCSI tries to log in, instruct Open-ISCSI to not perform login retries for that target. For this, set node.session.initial_login_retry_max for the target to 0. This setting is stored in Open-iSCSI's records under /etc/iscsi/nodes. As these records are overwritten with the defaults from /etc/iscsi/iscsid.conf on discovery, the setting needs to be applied after discovery. With this setting, one login attempt should take at most 15 seconds. This is still higher than pvestatd's iteration time of 10 seconds, but more tolerable. Logins will still be continuously retried by pvestatd in every iteration until there is a session to each discovered portal. Signed-off-by: Friedrich Weber Tested-by: Mira Limbeck Reviewed-by: Mira Limbeck --- src/PVE/Storage/ISCSIPlugin.pm | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/src/PVE/Storage/ISCSIPlugin.pm b/src/PVE/Storage/ISCSIPlugin.pm index 2bdd9a2..2e3d6ee 100644 --- a/src/PVE/Storage/ISCSIPlugin.pm +++ b/src/PVE/Storage/ISCSIPlugin.pm @@ -132,6 +132,20 @@ sub iscsi_login { eval { iscsi_discovery($portals); }; warn $@ if $@; + # Disable retries to avoid blocking pvestatd for too long, next iteration will retry anyway + eval { + my $cmd = [ + $ISCSIADM, + '--mode', 'node', + '--targetname', $target, + '--op', 'update', + '--name', 'node.session.initial_login_retry_max', + '--value', '0', + ]; + run_command($cmd); + }; + warn $@ if $@; + run_command([$ISCSIADM, '--mode', 'node', '--targetname', $target, '--login']); }