Voice of the DBA

Category: Blog

  • Learning Kubernetes Security Concepts

    This post continues looking at my process of learning more about Kubernetes. I’ve been working through the 50 days of Kubernetes (K8s). Here I continue on with a few videos on secrets, configuration management and RBAC.

    Secrets

    I am glad that the idea of storing data securely has come to so many applications. Authentication, authorization, privileges, and more are complex and hard to get right. We continually see problems with passwords, certificates, and the link not being managed well.

    Kubernetes has the concept of secrets, which can be values or file contents (like a certificates). These can then be sent or mounted to containers for use.

    One problem, these are stored in the Kubernetes etcd (keyvalue store) in an unencrypted format. Kubernetes has new concepts to integrate into key management areas, like Azure Key Vault, to protect secrets, though Kubernetes privilege controls are still needed.

    A gross simplification, but I learned a little more about what secrets are.

    Configuration Management

    This is interesting to me, because I like abstracting things away. In Kubernetes, we abstract a configuration object as a separate entity, which can then be applied to a container/pod later. This also works through deployments, allowing configurations to be part of the rolling deployment, which can prevent issues.

    If you have good testing/evaluation of what is healthy. This is likely easier than comprehensive unit testing, but still.

    A good idea, just not sure if this is too much.

    RBAC

    I always think of this as row-based, but it’s really role-based, so maybe that should be the way I translate RBAC in my head.

    Like most systems that use RBAC, there is, of course, a role. The video wanders a bit in the explanation, but I’ll try to summarize what I learned. There are two facets to roles. First, these are verb/noun pairs that determine what permission is available for what resource. Like get/list for the verb, and pod, volume, service, etc. for the noun. These are setting up the permission side.

    However, there is another facet. These roles can be set as cluster roles, similar to server roles for SQL Server, or at the namespace level, more like a database role. In either case, you are scoping permissions. Obviously, be careful with cluster roles.

    The other side of this is the user. We can have users or groups used for these roles, similar to what is in SQL Server.

    A simple explanation, but at least I have some idea of the concept.

  • Getting Downtime

    It’s been a crazy year, as are many of my years. I tend to like that, because I prefer to be busy rather than idle. That’s good, but I am aware of the dangers of doing too much, especially across time.

    Most of my travel comes from May-October, and I’ve had a lot this year. In that time frame, I’ve had 4 international trips already, with 2 more to come. To help deal with that, I know I need some breaks between trips.

    Last week I was in the UK for work, but I knew that I would get a little break this week. You might have seen that I’ve republished a few editorials as I was in Custer, S.D. this week. It’s a camping week with the family, and a chance for me to unwind with no real connectivity or responsibilities. A good break for me after a bit of travel.

    I decided to take off August this year from travel. I’m sad to be missing a few events (Louisville, Baton Rouge among them), but I need the downtime. I also take my daughter to university in  a couple weeks, so I’ve got a long weekend helping her move in and then touring New York state a bit with my wife.

    Like lots of IT people, I struggle to get away from work at times, so I’m making an effort to get better. You should as well.

  • Copy Files to a Docker Container

    One of the things that’s handy when working with containers is being able to move files in and out of the container. Certainly you can do this from a network share or other similar mechanism, but what about a straight copy?

    Docker has a command with the cp parameter to do this.

    docker cp WideWorldImporters.bak SQL17:/var/opt/mssql/data/WideWorldImporteres.bak

    The structure is the from:to, separated by a space as two parameters. If you’re going to the host, then just the path and filename, or just name if the current folder) for the file. For the container, you need the container ID or name with a colon (:) and then the relative path.

    A quick way to begin changing and customizing your containers by moving data in and out as needed.

  • Off-Topic Origem HS-3 Headphones Review

    I’m a big fan of music when I’m moving through life, and I use a lot of headphones. Between the gym, travel, and downtime between volleyball matches, I often have a pair with me. Actually, I often have a few pairs. In general I have tended to stick with wired models, but I do have a couple pairs of bluetooth models. I was contacted by Origem recently and asked if I would be interested in reviewing a pair of their HS-3 model. I agreed.

    The Pros: Great sound, physical control to easily pause/play, change volume, and change tracks. Lightweight and good battery life.

    The Cons: Bulky drivers noticeable and volume doesn’t quite get loud enough.

    Bottom Line: A good set of headphones, great connectivity, and waterproof. They seem durable across a few weeks, though time will tell if the headphones are worth the price.

    Initial Testing

    The headphones arrived charged. I powered them on and immediately they were looking to pair. I had my Garmin Forerunner 645 watch handy, and the pairing was smooth and quick. I know Bluetooth is getting better, and this was an example of how smooth the process was. I opened the settings on my phone, and with a long press on the volume, paired to that device as well.

    headphones_d

    I found it very easy to move between devices, though I did need to disconnect the headphones from the device. My phone had priority when connecting, but I think that’s likely because the watch doesn’t  automatically connect to anything.

    The headphones come with 4 different earpieces. I haven’t ever seen that, as most models seem to come with three. In this case, I had to try both the middle sizes to find the one that works best. It was a little hard for me to get the earpieces on the plastic bolt, but that’s likely me struggling to keep hold of the small rubber buds.

    There is a cord connecting the two headphones, which has a physical set of controls on the right ear. This is a long inline control pod on the wire. There is a center button that powers on/off (and pairs), we well as a button on each end that control volume (short press) or change tracks (long press). I found this to be easy to use throughout my testing and handy when at the gym and wanting to change a setting. It’s also nice to be able to pause quickly when someone tries to talk to me.

    The earpieces are different than anything I’ve seen. I do prefer those that hook over the year for security. I sweat a lot at the gym, and I never really have a great fit from the rubber inserts. I’m afraid of the Bluetooth separate buds that are all the rage as I have enough trouble with earbuds falling out while weightlifting or using the elliptical machine.

    In this case, there are wire over ear hooks, but they are on a swivel that allows me to put the rubber piece in my ear canal and swivel the hook down. I can also pop out the bud to hear better, and the hook allows the headphone to swing away, but remain secure.

    headphones_a

    The back of the wire has a rubber cover to reduce irritation, but the top loop is metal. I wish the rubber went a little higher, but I didn’t really have the irritation I’ve had with other Bluetooth mobile earpieces or even the other in-ear headphones I’ve tried. In fact, these have the most comfortable fit or the top/back of my ear.

    There is a small rubber fitting for the wire that allows you to shorten the wire and tighten the wire against your head. I found if I kept this tight for vigorous exercise, it worked great. If I had it at the loosest setting, when I turned my head, I felt a the wires pulling across the back of my neck. This has been a problem with quite a few pairs I’ve tried. These days I tend to keep the wire in front of my neck for general use.

    I listened to the headphones for about 2 hours on a gym trip, and they felt fine. The sound was good, and the headphones were comfortable. I was enjoying them for the first day.

    Longer Tests

    I decided to try these on a few longer outings and see how they worked. My family went to the mountains for the July 4 weekend, and I took these along, fully charged. I wore them during the two hour car trip up and they performed well. I left them in my bag July 4, but pulled them out for a longer test the next day. I was working from our vacation rental and planned to spent 6-7 hours that day listening to music.

    The headphones worked great for about 3 hours. Just before lunch, I’d get a slight dip in sound as a quiet voice let me know the battery was low. I let this continue for about 12 minutes before they cut off. A full charge, 2 hours in the car, a day+ in a bag, and then 3 more hours was pretty good.

    In other tests, it appears that a full charge is quick. I haven’t watched the charge indicator, but it does seem that about 30 minutes gets these charged. Six hours is what is claimed, and I have no reason to doubt these. I know I’ve used them close to six hours and they’ve worked well.

    The charging port on the inline control means I could actually charge these while listening to them, but it’s not comfortable (I tried). The charging cord weight will pull on one ear.

    Sounds Quality

    I’m not an audiophile, but I think these headphones sound great. There are large drivers that create deep, pleasant bass. Everything I hear is clear and crisp. I even had my kids and wife try this, and they all loved the sound.

    They also all noted that the headphones don’t get loud enough. No complaint about sound, just volume.

    Voice Control

    One of the features of the headphones is voice control. This is available to allow the user to perform the following functions:

    • pause
    • tracks
    • google assistant integration

    The FAQ says there is a caveat to this. If listening to music, the music must be stopped before using voice control. That means if I want to change the volume, I have to reach up and stop the music, putting by hand on the inline control. Right next to the volume control for the headphones.

    In some sense, this reduces the value of the voice control for me. In practicality, I have been able to say “Hey, VoiceIQ, Pause” while music is playing and it works. What I haven’t been able to get working is the restart of music. I also haven’t been able to easily get this to change tracks, or even launch the google assistant. It appears to sometimes work, sometimes not. Some of this might be dependent on whether the phone is unlocked or not, but I haven’t found a consistent method to the use of the feature.

    To be fair, I don’t love voice control of anything. It’s always weird to me, and in moving from Siri to Google, I find it to be less useful. Siri is fairly rigid in how it works, which I like, because I know what’s happening. Google I find more flexible, but also in that sense, less useful. This also might be the problem with music, in that iOS has tight integration with the music app. On Android, it’s a little looser.

    Conclusion

    These are nice headphones. They are very secure, a problem I’ve had with numerous pairs over the years. The sound is great, and they charge quickly. The downsides are the volume, the large drivers, and the cost. I don’t use the voice control much, and I think it’s a strange feature in many places, but you might feel differently.

    I’m not sure I’d pay $99 for these with all the other options out there, but I also wouldn’t rule it out. They are certainly cheaper than many of the other high end pairs, and they have stood up well across a month of use and travel for me. I’ll continue to use them over the next few months, with a few longer trips, and I’m looking forward to seeing how they perform.

    If you’d like to give these a try, Origem has a 30% off coupon. Use “L4IJLJPX” when you checkout.