We often talk about the climate impact based on greenhouse gases, but extracting fuel from the ground and using it in exothermal processes of course also releases energy as heat....
So, in one hour, the Earth receives more energy from the sun than us humans generate in an entire year. If we took all of the energy we generated over a year (and not just the waste heat) and converted it into heat, we wouldn't even be adding half of one percent to the system. Our direct contributions to the system are minuscule. The problem is we're pumping out green house gasses like there's no tomorrow. And those directly increase the amount of solar energy the Earth retains. And when we start keeping 1 or 2 more percent of that insane amount of solar energy, it adds up really, really fast.
Say a dissolvable spring is compressed with a bolt and nut that do not melt in a sulfuric acid solution. The spring has quite a bit of potential energy at this point since it is compressed. Assuming the spring dissolves perfectly (no breakage, just complete disintegration), what happens to the potential energy of the spring?
Assuming the spring dissolves perfectly (no breakage, just complete disintegration)
I think, eventually, this assumption breaks down. As the metal is dissolved away, the internal stresses in the spring will become greater than the remaining metal can hold, and the spring will break.
Fair enough, thinking about it at a microscopic level, individual molecules/atoms of material will be pushed into positions where they are being repelled from other atoms/molecules via electromagnetic forces. Those forces won't go away as the chemical reactions happen; so, I would guess that the answer is kinda the same as it is at the macroscopic level. When the bond which holds an individual atom in the lattice of the material is broken, those electromagnetic forces would push the resulting molecule away. So ya, it becomes heat.
I was wondering how often does one choose to make and keep back ups. I know that “It depends on your business needs”, but that is rather vague and unsatisfying, so I was hoping to hear some heuristics from the community. Like say I had a workstation/desktop that is acting as a server at a shop (taking inventory / sales...
While it’s true that “It depends on your business needs”, most often I’ve seen backup schemes which work on a minimum of a daily backup of most data. For example, on a larger, busier system, it might have a full backup done over the weekend when the system isn’t as busy and therefore has a lower business impact. Then daily differential backups are done each night. For smaller systems, it might just be a full backup of critical data every night.
For highly active, critical SQL databases, I’ve also seen this extended where the a full backup was done of the database weekly, with differential backups done nightly and transaction log backups done every 15 minutes. This obviously had full transactional logging turned on for the critical databases.
As a concrete example, on my home “server” (desktop with delusions of grandeur), the main data partition is running on ZFS with snapshots taken every 15 minutes, hourly, daily, weekly and monthly. The 15 min. snapshots are kept for an hour. Hourly snapshots are kept for 24 hours. Daily snapshots are kept for 31 days. Weekly snapshots are kept for 8 weeks. Monthly snapshots are kept for 12 months. There’s a bit of overlap in the daily and weekly schedules, as those are most likely to cover my arse from an “oops” factor.
The downside of the snapshot setup is that it doesn’t provide disaster recovery. And, I’ll admit, for my home stuff I haven’t gotten around to sorting this out. Ideally, I should be taking a weekly backup, compressing and encrypting it and pushing it to a cloud service somewhere. Laziness has meant that hasn’t been done yet.
Apparently they only sent 3 notification Emails, which a large number of their customers are reporting they never received. No one at InfluxData thought to do a scream test or even check the traffic levels to the region before deleting the data.
While this seems like something that absolutely should not have happened, it’s also a good reminder that “it’s in the cloud” does not mitigate the need for a good backup strategy. Maybe not the same level of on-site tape library backup solution many of us used to have; but, dumping the data onto a cold storage location on a different cloud on a regular basis would be a reasonable precaution.
We’re installing a new app on a secure network. The vendor has requested we allow access to gstatic.com. That seems overly broad to me and unsafe. Thoughts?
It comes down to the risk appetite of the business. You mention a “secure” network, but you already have internet access. So, it seems that some access to resources on the internet is already an accepted risk. Beyond the possibility that a random attacker might leverage the gstatic CDN to attack your network, do you have any other specific threats which make you hesitant to whitelist it? Are those threats large enough that the business would consider them to great a risk to that network? Do you have other mitigating controls in place? Would something like traffic inspection or endpoint protection be a sufficient mitigating control? Can the systems with the offending app be firewalled off from the rest of the network? Could the specific assets needed by cached internally and requests for gstatic redirected? What other compensating controls can be put in place to mitigate the risk?
All that said, have you brought the issued to your management and gotten their input on the risk? In the end, it’s a business decision and should be decided on by the business leaders. If they want to take the risk of allowing that network to access gstatic, that’s on them.
Working on a medium sized office network which only has a single PoE switch for WAPs. About 200 users. No copper to the desk… It made sense to buy a second PoE switch to give a bit of redundancy, even if it’s for manually swapping cables in case switch A dies....
But how will you manage your internal LAN from “the cloud” if your configuration isn’t created, stored and managed from “the cloud”? Surely, you aren’t some heathen who would rather not create the extra attack surface of having all that exposed to the internet? No, this is The Way. Cloudify ALL THE THINGS! No local configs. Trust “the cloud” to always be there. There has never been any example of service providers turning off cloud services and leaving users with expensive door stops. Nope, never. There is no Nest of products for which this had happened.
Sarcasm aside, never buy hardware which can’t be used without a proprietary cloud service. If you can’t turn those requirements off, then you don’t really own the device. You’re just renting it with a high, up-front activation fee and the requirement to handle disposal. Even worse, you get to go through all those costs again when the company decides you need to buy a new version.
Is the heat produced by fossil and nuclear fuel negligible?
We often talk about the climate impact based on greenhouse gases, but extracting fuel from the ground and using it in exothermal processes of course also releases energy as heat....
Spring Potential Energy
Say a dissolvable spring is compressed with a bolt and nut that do not melt in a sulfuric acid solution. The spring has quite a bit of potential energy at this point since it is compressed. Assuming the spring dissolves perfectly (no breakage, just complete disintegration), what happens to the potential energy of the spring?
How often do you make a back up?
I was wondering how often does one choose to make and keep back ups. I know that “It depends on your business needs”, but that is rather vague and unsatisfying, so I was hoping to hear some heuristics from the community. Like say I had a workstation/desktop that is acting as a server at a shop (taking inventory / sales...
InfluxDB Cloud shuts down in Belgium; some weren't notified before data deletion ( news.ycombinator.com )
Apparently they only sent 3 notification Emails, which a large number of their customers are reporting they never received. No one at InfluxData thought to do a scream test or even check the traffic levels to the region before deleting the data.
Is gstatic.com safe to whitelist on a secure network?
We’re installing a new app on a secure network. The vendor has requested we allow access to gstatic.com. That seems overly broad to me and unsafe. Thoughts?
[RANT] Why do I need an app to set up a switch?
Working on a medium sized office network which only has a single PoE switch for WAPs. About 200 users. No copper to the desk… It made sense to buy a second PoE switch to give a bit of redundancy, even if it’s for manually swapping cables in case switch A dies....