I have different sites running with 4 to 5 server at each location. All the locations have one monitoring server with Nagios. Now I want to create a central location and want to combine all the nagios services running at each location. Can anyone please point me to some documentation for these type of jobs.
There are two approaches that you can take.
Install a new Nagios core as you did at each location and perform active checks on each of the remote hosts. You'll likely end up installing NRPE on each of the remote hosts at each location and can read this document for the details: http://nagios.sourceforge.net/docs/nrpe/NRPE.pdf. If your remote servers are Windows servers, you can use NSClient to much of the same things that NRPE does for Linux hosts. This effectively centralizes your monitoring server. I also wrote some how-to style entries for using NRPE to run privileged commands http://blog.gnucom.cc/?p=479 or to run event handlers http://blog.gnucom.cc/?p=458. If you get tired of installing NRPE, you can use my script here http://blog.gnucom.cc/?p=185. I also have instructions to install NSClient here http://blog.gnucom.cc/?p=201.
Install a new Nagios core as you did at each location and perform passive checks by instructing the remote Nagios cores to feed their results to the new central Nagios core's passive command file. I haven't done this myself, so I'm going to point you to the communities documentation here http://nagios.sourceforge.net/docs/2_0/passivechecks.html. You could probably look at my event handler post to set up event handlers that send checks to the main server.
From my personal experience, the first option I mentioned is easier to implement, and is far easy to administer. However, as your server fleet grows you'll start seeing major CPU bottlenecks with the main Nagios core. This is where passive checks would become beneficial, as the main Nagios core simply waits for critical checks to be sent to it rather than having to check them itself.
Hope this helps. :)
A centralized view tool may be what you are looking for. There are a number of different options available.
Nagiosfusion
MK Livestatus
Nagcen
Thruk
Related
I am deploying active-active all in one in 2 separate servers with wso2-am 2.6.0 and wso2 analytics 2.6.0. I am configuring my servers by this link. In part 4 and 5 about rsync mechanism I have some questions:
1.how can I figure out that my server is working rsync or sync??
2.What will happen in future if I don't use rsync now and also don't use configuration on part 4 and 5 ?
1.how can I figure out that my server is working rsync or sync??
It is not really clear what are you asking for.. rsync is just a command to synchronize files in folders.
What is the rsync used for - when deploying an API, the gateway creates or updates a few synapse sequences or apis in the filesystem (repository/deployment/server) and these file updates need to be synchronized to all gateway nodes.
I personally don't advice using rsync, the whole issue is that you need to invoke regularly the rsynccommand to synchronize the files created by a master node. That creates certain delay for service availability and most important, if something goes wrong and you want to use another node as the master, you need to switch the rsync direction, which is not really automated process.
We usually keep it simple using a shared filesystem (nfs, gluster, ..) and then we have all active-active setup (ok, setting up HA NFS or glusterFS is not particulary simple, but that's usually job of the infra guys)
2.What will happen in future if I don't use rsync now and also don't use configuration on part 4 and 5 ?
In the case the filesystems between gateways is not synced or shared - you deploy an api from the publisher to a single gateway node, but other gateway nodes won't create the synapse sequences and api artefacts. As a result the other nodes won't pass the client request to the backend
From what I gather, the only way to use a MySQL database with Azure websites is to use Cleardb but can I install MySQL on VMs provided in Azure Cloud Services. And if so how?
This question might get closed and moved to ServerFault (where it really belongs). That said: ClearDB provides MySQL-as-a-Service in Azure. It has nothing to do with what you can install in your own Virtual Machines. You can absolutely do a VM-based MySQL install (or any other database engine that you can install on Linux or Windows). In fact, the Azure portal even has a tutorial for a MySQL installation on OpenSUSE.
If you're referring to installing in web/worker roles: This simply isn't a good fit for database engines, due to:
the need to completely script/automate the install with zero interaction (which might take a long time). This includes all necessary software being downloaded/installed to the vm images every time a new instance is spun up.
the likely inability for a database cluster to cope with arbitrary scale-out (the typical use case for web/worker roles). Database clusters may or may not work well when a scale-out occurs (adding an additional vm). Same thing when scaling in (removing a vm).
less-optimal attached-storage configuration
inability to use Linux VMs
So, assuming you're still ok with Virtual Machines (vs stateless Cloud Service vm's): You'll need to carefully plan your deployment, with decisions such as:
Distro (Ubuntu, CentOS, etc). Azure-supported Linux distro list here
Selecting proper VM size (the DS series provide SSD attached disk support; the G series scale to 448GB RAM)
Azure Storage attached disks being non-Premium or Premium (premium disks are SSD-backed, durable disks scaling to 1TB/5000 IOPS per disk, up to 32 disks per VM depending on VM size)
Virtual network configuration (for multi-node cluster)
Accessibility of database cluster (whether your app is in the vnet or accesses it through a public endpoint; and if the latter, setting up ACL's)
Backup / HA / DR planning
Someone else mentioned using a pre-built VM image from VM Depot. Just realize that, if you go that route, you're relying on someone else to configure the database engine install for you. This may or may not be optimal for what you're trying to achieve. And the images may or may not be up-to-date with the latest versions, patches, etc.
Of course, what I wrote applies to any database engine you install in your own virtual machines, where a service provider (such as ClearDB) tends to take care of most of these things for you.
If you are talking about standard VMs then you can use a pre-built images on VMDepot for that.
If you are talking about web or worker roles (PaaS) I wouldn't recommend it, but if you really want to you could. You would need to fully script the install of the solution on the host. The only downside (and it's a big one) you would have would be the that the host will be moved to a new host at some point which would mean your MySQL data files would be lost - if you backed up frequently and were happy to lose some data then this option may work for you.
I think, that the main question is "what You want to achieve?". As I see, You want to use PaaS solution with Web Apps or Cloud Service and You need a MySQL database. If Yes, You have two options (both technically as David Makogon said). First one is to deploy Your own (one) server with MySQL and connect to it from the outside (internet side). Second solution is to create one MySQL server or cluster and connect Your application internally in Azure virtual network. WIth Cloud Service it is simple but with Web App it is not. You must create VPN gateway in Azure VM and connect Your Web App to this gateway. In this way You will have internal connection wfrom Your application to Your own MySQL cluster.
For our customer the application which is running is using MySQL database. However, this server is without monitoring. I want to install OpenNMS (which uses PostgreSQL) application to monitor the solution and send the traps to main NMS system.
Is there any problem having both on the same server?
No, there is no technical problem. Both default to different ports they listen on.
The only problem that could arise is that each individual DB might be slower compared to an installation on separate phyiscal machines because they are both share (and fight for) for the same resources (I/O, memory, CPU, network, ...)
I want to configure mysql proxy on my test environment to observe the below.
1. Behavior of the proxy
2. How load, CPU usage varies on my test server for read/write distribution.
I googled and able to install proxy on my ubuntu linux.
But I didnt see any thing on configuring it in a step by step manner and how to start or stop this.
Shall some one explore on this and this would be of great help for me.
Thanks in advance
Regards,
UDAY
By default if you run the proxy on the same machine as the server it will listen to port 4040 and query a backend server on the msyql default port of 3036. Other port numbers and server locations can be configured from the command line or with a configuration file.
To distribute queries across servers, add monitoring, profiling etc. you need to provide a Lua script to mysql-proxy. See the example / tutorial scripts in /usr/local/share/docs that came with the installation download. There is work to do for a production implementation.
The basics of how the scripting works can be found here under MySQL Proxy Scripting.
Don't be worried about Lua. The syntax is quite readable given the tutorial examples to work from. As and when you need it lua.org has more details of Lua.
We have a Java EE application (EAR file deployed on JBoss, MySQL, MongoDB) which we would like to deploy on an Amazon EC2 instance. I have several questions regarding deployment best practices.
What is the most commonly used Linux AMI which we can rely on for a robust deployment (There are so many Linux variants, and I am not sure which AMI is commonly used, is it Fedora, CentOS, Red Hat, SUSE ...)
How do we handle production upgrades (EAR file modifications or schema upgrades). Are there any tools which are available to handle this installation or rollback of these changes.
What kind of data backup capability is available for the database?
Should I rely on Amazon RDS for MySQL support?
How should I handle support for MongoDB?
This is the first time, I am hosting an web-app and would appreciate some inputs on how to manage the production instance.
I agree with Mark Robinson's answer: Use whichever Unix variant you're most comfortable with. It may pay to pick one with decent cloud support. For my site I use Ubuntu.
I have a common image which is the base of every version deploy I do. I have www.mysite.com pointing to an Elastic IP so I can decide which instance it goes to. The common image has all the software I need installed (Postgres/Postgis/Tomcat/etc) but the database and web server data folders and symlinked to Elastic Block Store (EBS) instances.
When it comes time to do a deploy I start a new instance up, freeze and snapshot the EBS volumes on production and make new volumes. I point my new instance at the new volumes and then install whatever I need to onto that. Once I've smoke tested everything successfully I can switch the Elastic IP to point to the new instance and everything keeps on going.
I'll note that I currently have the advantage where only I can modify the database; no users can. This will become a problem shortly.
If you use the XFS filesystem on top of the EBS volume then you can tell XFS to freeze the file system (so no updates happen) then call the EC2 api to snapshot the volume then unfreeze the file system. The result is that the snapshot is taken quickly and sent to S3. I have a nightly script which does this.
If RDS looks like it will suit your needs then use it. Amazon is building lots of solid tools quickly and this will ease your scalability issues if you have any.
I'm sorry, I have no idea.
Good question!
1) I would recommend going with whatever Linux variant you are most comfortable with. If you have someone who is really keen on CentOS, go with that. Once you have selected your AMI, take it and customize it by configuring how you want it. Then save that AMI as you base-layout. It will make rolling out new machines much easier and save your bacon if EC2 goes down.
2) Upgrades with EC2 can be tres cool. Instead of upgrading a live system, take your pre-configured AMI, update that and save that AMI as myAMI-1.1 (or whatever). That way, you can flip over to the new system almost instantly AND roll back to a previous version in case something breaks. You can also back-up DB instances to S3. It's cheap at about $0.10/GB/Month.
3) It depends where you are storing your DB. If you are storing it on your EC2 instance you are in trouble. The EC2 instances have no persistence storage. So if your machine crashes, you lose everything. I'm not familiar with Amazon DB system but you should also look into Elastic Block Store. It's basically an actual hard-drive you can write to. When you want to upgrade your schema, do a full DB dump to S3 and then do an upgrade of your actual schema. If something goes wrong, you can pull the previous version out of S3.
4) & 5) I have never used those so I can't help you.
What is the most commonly used Linux AMI which we can rely on for a robust deployment (There are so many Linux variants, and I am not sure which AMI is commonly used, is it Fedora, CentOS, Red Hat, SUSE ...)
How do we handle production upgrades (EAR file modifications or schema upgrades). Are there any tools which are available to handle this installation or rollback of these changes.
What kind of data backup capability is available for the database?
Should I rely on Amazon RDS for MySQL support?
How should I handle support for MongoDB?
Any Linux AMI will do the job, what you need is a JRE only. (assuming development work not required). If you need to monitor the JVM behavior then get JConsole installed.
Easiest and painless way is to SSH into the local home directory, transfer the updated class file/EAR file (depends the number of changes applied) and copy and replace into the Tomcat deployment directory, restart apache. (make sure you tested locally before upload to production).
Depends on which database you are using, if you are using MySQL then just do scheduled backup that writes to your home directory so that from time to time you could SSH in and download a copy for backup purpose.
I would not consider reply on Amazon RDS for MySQL support due to 2 reasons: MySQL is small enough and manageable, and also I would want to have total complete control of the database and why pay for more when you can do it yourself FOC?
The usage of MongoDB should be align with the purpose of your application and benefits you gain from that. I would recommend you use MongoDB for static data retrieval like state, country, area etc... where MySQL to be use for transaction data only.
If you can live with deploying your Java EE application on TomEE instead of JBoss, Boxfuse does what you want.
For you Java EE application you literally only have to execute (TomEE uses war files instead of ear files):
boxfuse run my-tomee-app-1.0.war -env=prod
This will
Create AMI containing TomEE and your application ready to boot
Create an Elastic IP or ELB
Create a security group with the correct ports defined
Create an auto-scaling group
Launch your instance(s)
Any subsequent update will be done as a zero downtime blue/green deployment.
More info: https://boxfuse.com/blog/javaee-aws