I have a device that is failing. Using ddrescue, I have recovered all all but about 500 KB in 83 regions. The map file tells me the raw offset and length of each lost region. I want to find out what files are affected. How can I obtain a list of physical sector offsets associated with a file on an exFAT volume?
I am running Ubuntu 24.04 using ZFS for my filesystems. This is on a laptop whose only storage device is a WD Black SN850X NVMe card. The default Ubuntu installation process configured two ZFS pools:
capacity operations bandwidth
pool alloc free read write read write
-------------------------------------- ----- ----- ----- ----- ----- -----
bpool 187M 1.69G 0 0 381 204
86349523-abd9-7a45-ab84-60d7622c240f 187M 1.69G 0 0 381 204
-------------------------------------- ----- ----- ----- ----- ----- -----
rpool 286G 634G 13 31 1.11M 796K
cc31ec4d-1dd2-ed4f-9f90-fa99ec5aa3a2 286G 634G 13 31 1.11M 796K
-------------------------------------- ----- ----- ----- ----- ----- -----
/tmp is part of the root mount, which is in rpool.
My /tmp folder briefly had over 2 million files in it due to a bug in some code. When there were this many files in it, performance took a nosedive -- even just listing files (without sorting) would pause for upwards of a second. I removed most of the files, and things are back down to a manageable level now. But, operations on the list of files in /tmp are still slow.
When I time ls --sort=none on e.g. /bin, which has 2,842 entries it, I get something like:
real 0m0.088s
user 0m0.001s
sys 0m0.075s
But the same command on /tmp, which currently has 4,444 entries:
real 0m0.472s
user 0m0.007s
sys 0m0.446s
It seems that briefly housing 2 million files has left a permanent impact on the structure of /tmp? Is there a way to fix this? Do I just need to make a new /tmp and cut over to it??
I have a webcam connected to a FreeBSD server that I want to collect and email an image on a schedule via a cron job. The room it is in may not always be lit. I am hoping to find some solution where a light can illuminate the subject just at the time of the photo. As a first stab, I bought a cheap USB lamp from Amazon and then tried using usbconfig to power off its port, but alas, this had no effect on the lamp. (Also, the port seemed to disappear permanently and could no longer be addressed by usbconfig -- probably something I just don't understand about the process.)
This server is running FreeBSD 12.1. Does anyone know of a reliable and affordable way to do what I need?
I've recently configured a VM on a low-end rental VPS service to try to improve load times for a web site I'm running. (The web site makes use of high-reliability technologies that require full access to a VM, so I can't just use cheap IIS site hosting.) I've got it all set up, and it's working well (and way faster than my cable modem :-) with one caveat, and it's an odd one.
The VPS doesn't seem capable of receiving inbound traffic unless it has just recently sent an outbound packet. So, if the server is just sitting there, and I'm connected to the "KVM" VNC connection, I can use the system, it's fully responsive, but it doesn't respond to pings or connection attempts on its Internet interface. As soon as I initiate some network traffic from the VPS outbound, such as ping requests, browsing a web page, downloading OS updates or what have you, then suddenly it starts getting & replying to pings. As soon as the outbound traffic drops off, the site drops off the Internet again.
The site is up and running right now only because I have an ongoing "ping" operation in a console window hitting another IP of mine. One outbound ping a second seems to keep the site pretty much accessible.
It seems very odd to me that the inbound traffic should be contingent on outbound traffic in this way. The VPS provider assures me it's nothing they're in charge of -- but then at the rates I'm paying I don't know if I expect them to understand every last detail of the service they're offering. :-)
Has anyone heard of this sort of behaviour before?
Here are all of the configuration details I know that I can think of, off the top of my head: