Authentication in MongoDB provides ‘normal’, which is full read and write, or ‘readonly’ access at a database level. There are two scenarios when authentication comes into play: single server and multi-server. When using a single server, authentication can be enabled but adding --auth to the startup parameters. When using a replicaset, sharded setup or combination, a key file must be provided and the --keyFile parameter used at startup. This enables each node to communicate with other nodes using a nonce scheme based on the keyFile. In this configuration, --auth is implied and the......
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I’ve been working on some HP-UX systems recently and had way too much trouble finding the solution to an issue with how vi, top and other functions displayed in the terminal. For example, when I would start vi rather than blanking the screen, it would just overwrite the lowest line in the terminal with 23y0C1A0y0C~0y0CC56C64C72C. It appeared that vi commands would work, but I couldn’t see anything that was happening. My initial attempt at setting the term failed to produce any results. The final solution is pretty easy: I changed my shell to......
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Last week I spent way too much time integrating Apache Wicket and Google Guice. Yikes! The most difficult part for me was getting the initialization to happen in the right order. A big Thank You to Dan Retzlaff on the Wicket list for helping work through these details. The details below were applied to a Wicket quickstart project for Wicket 6.0.0. Design Decisions It was important to me to keep the application tier separate from web tier. I actually maintain each in a separate repository. I have several motivations for this, such as:......
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Security in MongoDB is relatively young in terms of features and granularity. Interestingly, they indicate that a typical use case would be to use Mongo on a trusted network “much like how one would use, say, memcached.” MongoDB does NOT run in secure mode by default. As it is, the features that are available are standard, proven and probably sufficient for most use cases. Here’s a quick summary of pros and cons. Pros Nonce-based digest for authentication Security applies across replica set nodes and shard members Cons Few recent replies on security wiki......
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I’ve been refactoring an application recently to move away from a proprietary and inflexible in memory datastore. The drawbacks of the proprietary datastore included the fact that the content was static. The only way to update data involved a build and replication process that took much longer than the stakeholders were willing to wait. The main selling point in favor of the in memory datastore was that it is blazing fast. And I mean blazing fast. My choice for a replacement datastore technology is MongoDB. MongoDB worked great, but the profiling and performance......
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The information below was delivered to one of my programmers as direction for how to implement a rather big change in an existing software product that I sell. I thought it was potentially useful to a broader audience, so I’m posting it here: …The rest of this is rather complicated to explain online. I’ll do my best. I’m going to look at this in a simplistic way and let you work through the details. First imagine that we have an Authorize.net processing class based largely on their API. class AuthnetProcessAIMPayment { protected $apiKey;......
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One of my applications runs on a large assortment of hosts split between various data centers. Some of these are redundant pairs and others are in load balanced clusters. They all require a set of identical files which represent static content and other data. rsync was chosen to facilitate replication of data from a source to many targets. What rsync lacked out of the box was a reporting mechanism to verify that the collection of files across target systems was consistent with the source. Existing solutions Before designing my solution, I searched for......
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Last week I completed three days of training and took the certification test for Scrum Master. About 70 percent of the material was rehash, but I did pick up a few new bits during the training. Lately I’ve been reading Speed of Trust and so the effect trust has on the Scrum process kept coming to mind. I can see how trust between the Product Owner and the Development Team is a strong influencer to the success of Scrum. For example, the Product Owner has to prioritize the backlog and trust that the......
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Several years ago I hosted with webfaction for about a year. I was drawn to them at the time because they allowed SSH access and I could run Java applications on my account. Those were not common features available under shared hosting at the time. I didn’t end up deploying any Java applications and the PHP sites I did deploy routed through webfaction’s nginx to PHP configuration which frequently failed. That meant that many visitors to my site saw nginx errors rather than my web page. When they couldn’t resolve the issue I......
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Today I needed to install subversion on a Linux host on which I don’t have root access. With root access the install would have been very simple. However, I couldn’t find a good tutorial showing how to go about installing the software just for the local user. This post goes through how I did that. Requirements Subversion relies on several third party libraries. Some of these may already be available on your server. Others may not be, so you’ll need more than I show here. What I provide should give you a roadmap......
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