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If you only have a master then you have no HA. You're just not resilient to failovers. If you have a master/slave setup then as John mentioned you can run an Arbiter instance that is just used to determine the coordinator based on the quorum. To answer your question, I think you'd need to have a Powershell script that would create a neo4j.properties and ...


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I found that I need. Adding the parameter "-V" in the file "/etc/default/keepalived" keep the VRRP and VIPs on daemon stop. I need this for the configuration changes on our production environment. Thanks!


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Solution Thanks to the folks that investigated with me, I was able to find the solution to my problem and I do now have a working setup. If you feel brave enough, you can read the comments on the original question, but here is a summary of the steps that helped me solve my issue. Read the source First thing to do when setting up HA resources, will sound ...


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After reading your comment I'm not sure if you still want to go that route you had planned for originally, but anyway, here is an input for this: Using crm_mon --group-by-node -1 you could get a "one-time" view of the current state of your cluster, grouped by your nodes. The -1 parameter makes this non-interactive, which means it just displays the data and ...


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The issue turned out to be painfully obvious once I slept on it and took a second look (aren't they always). It was as simple as there being a typo in the unicast_src_ip. Since the IP was incorrect, no messages were going through on either server. I would have thought there'd be some error message for this, but everything started working 100% once this was ...


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Your netcat command is trying to use port 112, not protocol 112. That's why it doesn't work. Also, using netcat to test comms in this case is not the right way to go. Use either of these commands to see if your traffic is present on either instance: tcpdump "ip proto 112" tshark -f "vrrp" Your configs should define one of the servers as MASTER, the other ...


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See: Should VMware HA Admission Control be enabled for small (2/3-host) clusters? Don't enable admission control for a 2-host environment. Unless you're dealing with well-calculated or custom slot sizes or VMs or resource pools with reservations, there's no benefit to doing this.


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Yes it is, but you'll need to use some sort of reliable fencing/stonith; this will trigger a reboot of one node when you pull the network, allowing it to rejoin on startup: http://clusterlabs.org/doc/crm_fencing.html Fencing is a very important, and often overlooked, concept in clustering. You should also look into configuring redundant ring support in ...


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Yes, if you have software assurance you can still have a warm standby. (It used to be that you could have one without software assurance as long as you weren't querying it, but that changed with 2014.) It sounds like what you're looking at is AlwaysOn Availabilty Groups, but do check the licensing (as Steve Mangiameli said in comments). (Particularly: If ...


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I'm gathering you're looking to roll both high availability and some kind of load-balancing into one system. There is only really one way you can kind of achieve something like this with a SQL Server 2014 Availability Group and it isn't exactly what you noted: Readable Secondary Replica https://msdn.microsoft.com/en-AU/library/ff878253.aspx The ...


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We had 2 problems: 1) We had one mysql query that used three joins. Turns out this function was crashing Mysql. We rewrote this query to use 4 mysql queries without joins and that solved that problem. (Bit of a hot-fix, we will probably rewrite the function so it is possible to cache it). 2) We were experiencing around 99.9 % I/O wait when we only used 10% ...


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So we figured out the problem. It was, as it often is, the database server. We had 2 problems: 1) We had one mysql query that used three joins. Turns out this function was crashing Mysql. We rewrote this query to use 4 mysql queries without joins and that solved that problem. (Bit of a hot-fix, we will probably rewrite the function so it is possible to ...



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