20.04.2012 03:09, Andrew Beekhof wrote: > On Thu, Apr 19, 2012 at 11:51 PM, Dan Frincu <df.clus...@gmail.com> wrote: >> Hi, >> >> On Thu, Apr 19, 2012 at 3:56 PM, Parshvi <parshvi...@gmail.com> wrote: >>> 1) What is the use of ssh without pass key between cluster nodes in >>> pacemaker ? >>> a. Use case: >>> i. Two nodes in a cluster (Call them Node-1 and Node-2) >>> ii. One interface configured in corosync.conf for its heartbeat or >>> messaging. Eg. Bind net addr : 192.168.10.0 >>> iii. Another interface configured in /etc/hosts for hostname resolution. >>> Eg. IP: 192.168.129.10 Hostname: Node-1 >>> Eg. IP: 192.168.129.11 Hostname: Node-2 >>> iv. Hence for all ssh communication between the two nodes, hostname >>> resolves >>> to subnet 129 address. >>> v. 12 services configured in active/passive mode >>> vi. 1 service configured in master/slave mode >>> vii. 8 services are non-sticky (they failback) in active/passive >>> viii. 4 services are sticky (do not failback) in active/passive >>> ix. Distribution: Node-1 is primary for 8 services (of which 4 are non- >>> sticky), Node-2 is preferred for 4 services of a total 12 (non-sticky) >>> >>> b. Observations: >>> i. On Node-2, the interface was down over which IP: 192.168.129.11 >>> Hostname: >>> Node-2 was configured. >>> ii. On Node-1 all interfaces were up. >>> iii. Interface used by corosync for hearbeat/messaging was up at all >>> times >>> (Bind net addr : 192.168.10.0) >>> iv. In crm_mon: Node-1 sees Node-2 as offline >>> cibadmin --query fails to work (remote node did not respond) >>> v. In crm_mon: Node-2 sees Node-1 as online >>> vi. All the services were seen active on Node-1 (including those that >>> were >>> preferred for Node-2). Observed in crm_mon output. >>> vii. 4 services for which Node-2 was preferred were seen active Node-2 >>> also >>> (hence 4 services active on both the nodes). >>> Observed in crm_mon output: Only 4 services were shown active, the >>> status of >>> the rest of the services active on Node-1 did not reflect in crm_mon >>> Even though crm_mon on Node-2 sees Node-1 as “online”. >>> c. Errors in log file: >>> i. On Node-2: >>> 1. Resource ocf::RscRA:rsc appears to be active on 2 nodes >>> 2. The above error appears for all the resources configured in >>> pacemaker. >>> >>> >>> Query: >>> 1) For what purpose does Pacemaker require “ssh without a pass key” to be >>> enabled between the nodes in a cluster ? >> >> scp > > But pacemaker doesn't use scp... or is this in relation to the > clusters from scratch document? > -ECONFUSED
hb_report? > >> >>> 2) For what purpose does Pacemaker use Node “hostname” for ? how Node >>> “hostname” >>> come into picture ? >> >> When choosing where to allocate resources not explicitly tied to a node. See >> >> http://www.clusterlabs.org/doc/en-US/Pacemaker/1.1/html-single/Pacemaker_Explained/#node-score-equal >> >> and >> >> http://www.clusterlabs.org/doc/en-US/Pacemaker/1.1/html-single/Pacemaker_Explained/#_background >> >>> 3) Let’s say in a two node cluster two communication paths are available >>> between >>> the two nodes. >>> a. Eth1 and eth2. >>> b. The hostname of the node resolves to IP Address on eth1. >>> c. Consider, eth1 (network cable disconnected) goes down. >>> d. Eth2 is up, but hostname does not resolve to the IP on eth2 (resolves to >>> eth1 addr). >> >> Inter-node communication is usually specified by IP address, and >> redundant connections (as in your case) is recommended. >> >>> e. Will this (hostname) have any issue ? >>> >>> >>> >>> >>> _______________________________________________ >>> Pacemaker mailing list: Pacemaker@oss.clusterlabs.org >>> http://oss.clusterlabs.org/mailman/listinfo/pacemaker >>> >>> Project Home: http://www.clusterlabs.org >>> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf >>> Bugs: http://bugs.clusterlabs.org >> >> >> >> -- >> Dan Frincu >> CCNA, RHCE >> >> _______________________________________________ >> Pacemaker mailing list: Pacemaker@oss.clusterlabs.org >> http://oss.clusterlabs.org/mailman/listinfo/pacemaker >> >> Project Home: http://www.clusterlabs.org >> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf >> Bugs: http://bugs.clusterlabs.org > > _______________________________________________ > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: http://bugs.clusterlabs.org _______________________________________________ Pacemaker mailing list: Pacemaker@oss.clusterlabs.org http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org
