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Making a Linux home server sleep on idle and wake on demand – the simple way

dgross.ca

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Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#191

Post by fuzzy2 »

DCKing wrote: post #33

This looks like one of those home server infrastructure setup rabbit holes I would've bailed out of within the first 10 minutes of Googling to research the problem. I commend the author for their perseverance and the writeup - rabbit hole writeups are their own form of entertainment. That alone was worth it. I could never run anything that looks like such a conceptual pain the butt. A pain to maintain and troubleshoo…

I think it’s not too bad. Of course, I knew most of the ingredients before reading this article. I think my Router OS router can also do the ARP thing.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#192

Post by gambiting »

hulitu wrote: post #181
DCKing wrote: post #33

This looks like one of those home server infrastructure setup rabbit holes I would've bailed out of within the first 10 minutes of Googling to research the problem. I commend the author for their perseverance and the writeup - rabbit hole writeups are their own form of entertainment. That alone was worth it. I could never run anything that looks like such a conceptual pain the butt. A pain to maintain and troubleshoo…

> A Raspberry Pi that itself would work just as fine as the Time Machine server the author seems to need on demand? A Raspberry Pi has one big problem: no SATA ports.

Yes but RPI 4 has usb 3.0 ports that you'd really struggle to saturate with a gigabit connection - I used to see the lack of sata as a major problem with that platform but nowadays it really doesn't matter.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#193

Post by fuzzy2 »

rendaw wrote: post #121
DCKing wrote: post #33

This looks like one of those home server infrastructure setup rabbit holes I would've bailed out of within the first 10 minutes of Googling to research the problem. I commend the author for their perseverance and the writeup - rabbit hole writeups are their own form of entertainment. That alone was worth it. I could never run anything that looks like such a conceptual pain the butt. A pain to maintain and troubleshoo…

You could have an Arduino to wake the Pi.

But then, why not just use an ESP32 which can replace the Pi entirely in the proposed setup. ;-)

I would have an ESP32 impersonate the MAC address of the server passively (ie. only in the Wi-Fi association), then “push the wake button” if it found traffic that is allowed to wake the server. A wake-up firewall, if you will.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#194

Post by r1ch »

heywire wrote: post #155
r1ch wrote: post #99

Earlier quoted context omitted.

Try connecting to an SSH server for more than a few hours without passing traffic and then have the server be the one to send a message. Oops! Your ISP tore down the NAT association and you have no idea the server isn't sending anything until you try to communicate with the server and get a timeout / RST. NAT breaks TCP, but at least with consumer NAT you're in control of the timeouts on your router. With CGNAT you'r…

I actually used to have that issue years ago at work. To work around that I just enabled a keepalive (ServerAliveInterval maybe?) setting in my ssh config. I don’t connect to any ssh servers outside my house for long periods of time, so I haven’t encountered that. Thanks for the heads up, good info!

OpenSSH does enable TCP keepalives by default so that it can detect and close dead connections, but the keepalive interval is far too high to work around bad NATs.

Kind of related to the OP, I spent a decent amount of time trying to have my SSH sessions survive a sleep on Windows. With keepalive disabled, proper Wi-Fi adapter sleep behavior and long enough DHCP leases, I was able to put my PC to sleep and come back the next day and still have my sessions active on resume. Unfortunately it wasn't too practical to disable keepalive as sessions that really do crash never get cleaned up.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#195

Post by __turbobrew__ »

The simple way is paying $9.99/month for 2TB of iCloud space and put your Time Machine backups there.

Home labbing can be fun and a good way to learn, but if you are just trying to back up your files you cannot beat the economies of scale and reliability of cloud providers.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#197

Post by gh02t »

nottorp wrote: post #175
manmal wrote: post #170

Earlier quoted context omitted.

The N100 has a TDP of 6W. I haven't measured power draw of the whole system yet though, I imagine that the mainboard will pull another couple watts at least. It shines especially in scenarios where the Pi is just a tad too slow. E.g. you can't live transcode 4k videos on a Pi, while the N100 has latest UHD graphics and therefore ships with a decent HW-accelerated H265 en/decoder.

There are a lot of low power media boxes but few servers sadly. By server i mean multiple network ports and storage ports, space in the case for several spinny discs in addition to the ssds etc. I doubt any NUC is good for a server by my definition.

Sure there are, there are lots of NAS appliances boxes from the likes of Synology/QNAP/Aliexpress Special that can run double duty as servers built on similar low power CPUs. Some of them even have decent networking options.

The problem is that a lot of the commercial products are woefully underspecc'ed for the price and you outgrow them quickly. Spinning disks also eat a lot of power, relatively speaking, so they kind of eat into the "low power" usecase.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#198

Post by [deleted] »

nottorp wrote: post #175
manmal wrote: post #170

Earlier quoted context omitted.

The N100 has a TDP of 6W. I haven't measured power draw of the whole system yet though, I imagine that the mainboard will pull another couple watts at least. It shines especially in scenarios where the Pi is just a tad too slow. E.g. you can't live transcode 4k videos on a Pi, while the N100 has latest UHD graphics and therefore ships with a decent HW-accelerated H265 en/decoder.

There are a lot of low power media boxes but few servers sadly. By server i mean multiple network ports and storage ports, space in the case for several spinny discs in addition to the ssds etc. I doubt any NUC is good for a server by my definition.

[deleted]

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#199

Post by TacticalCoder »

DCKing wrote: post #33

This looks like one of those home server infrastructure setup rabbit holes I would've bailed out of within the first 10 minutes of Googling to research the problem. I commend the author for their perseverance and the writeup - rabbit hole writeups are their own form of entertainment. That alone was worth it. I could never run anything that looks like such a conceptual pain the butt. A pain to maintain and troubleshoo…

> Especially since the setup requires a Raspberry Pi to run permanently.

Which they'll gladly do no?

If (poor quality) SD card corruption is a concern, you can have the RPi mount the SD card read-only or just keep a full backup of the SD card.

I've had a RPi 1 power 4 VoIP Cisco phones for years. Zero issue.

I've got another one constantly establishing a remote SSH-tunnel so that I can easily troubleshoot my brother, who lives in another country, 's LAN. The uptime is more than a year.

One is routing (well, doing SNAT really) and firewalling between two non routable LANs. I set up the thing once and it's so reliable there's neither a screen nor a monitor hooked to it: just the power adapter and two ethernet cables (including one in a USB-to-ethernet adapter).

Another one is running unbound. Same: no monitor, no keyboard, no nothing. The power adapter and one ethernet cable. Simple. Not much can go wrong. No moving parts. It's happily null routing hundreds of thousands of crappy domain names 24/7.

I've got another one in a vintage arcade cab with a Pi2JAMMA adapter. In years it never failed to boot once. As we the others, just in case, I still have a "dd" of the entire SD card. Should something happen I'd just dd the image to a new SD card.

The shortage of RPi is apparently due to companies snapping them all for industrial uses.

I haven't heard of many people complaining "my RPi died overnight" (unlike, say, the Apple M1 laptop's screens).

They're incredibly reliable pieces of equipment for their gentle price. In case something goes wrong on one of mine, I just have a dump of the entire SD card.

I don't disagree that they may be a pain in the butt to set up, just like any server. But once setup, they don't move under your feet so the maintenance is really minimal.

I hate that there's a shortage of Pi but I'm not sure that criticizing them as "non reliable" is a criticism made in good faith.

Re: Making a Linux home server sleep on idle and wake on demand – the simple way

#200

Post by ape4 »

jeffbee wrote: post #149
aequitas wrote: post #59

Earlier quoted context omitted.

I agree, but you could argue that the Raspberry Pi is not performant enough during restores or browsing the backups. During the backup itself performance should not have to be that big of an issue as it's mostly a background operation you will not be waiting on. You could also use the RPi as a stepping stone which syncs it's files to the 'real' backup server which is on a daily/weekly timer instead of on-demand setup…

> power hungry server running 24/7 Nothing in this article supports this statement. It just says "high power consumption" without measuring, and declares victory without measuring the power saved. The fact is that power scaling has almost erased the difference between "suspended" and just "idle", to such an extent that there might not even be a meaningful difference, or any measurable difference. My NUC 12 Pro is dra…

My first thought too. Reports can show the power usage for each process. So reduce the power-hungry processes. Or schedule them for lower cost times of day.
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