Strange Raspberry PI SD card behaviour - raspberry-pi

My raspberry 1 pi has raspbian on Sandisk Extreme 32GB.
It is working well in the Raspberry, OS boots, no problem, however, if I shut it down, and insert into ubuntu laptop, I see error JBD2: Error -5 detected when updating journal superblock for sdb2-8. and I cannot read it.
First time I noticed a year ago. Raspberry pi still working without a problem.

More details would help to identify your problem more accurately.
But it souds like you may have to run fsck in order to fix filsystem errors.
here is an example for running fsck if your partition is on sdb2 :
sudo fsck /dev/sdb2
It's always recommended to take a backup first.

Related

Importing large Bson file to mongo db in raspberry pi

I am trying to import a very large BSON file (15Gb) to mongodb. I am using a raspberry pi 3b+ (it has a 1Gb of ram).
The problem I am running to is that when I execute the mongorestore command to import the bson, the process is killed.
I have tried to add swap using a usb (6Gb added) but the problem persists, the error displayed is related to lack of ram.
Executing the command in a Ubuntu Virtual Machine with 8Gb ram shows no problem.
Thanks

./pintos run alarm-multiple command not creating threads

I have ubuntu version 18.04.3 running on virtual box.
I have been trying to install pintos on qemu, but when I run ./pintos run alarm-multiple my qemu is stuck on loading.
I am getting the following output:
**WARNING: Image format was not specified for '/tmp/5XpQ2ee16J.dsk' and probing guessed raw.
Automatically detecting the format is dangerous for raw images, write
operations on block 0 will be restricted.Specify the 'raw' format
explicitly to remove the restrictions.
qemu-system-x86_64: warning: TCG doesn't support requested feature:
CPUID.01H:ECX.vmx [bit 5]
PiLo hda1
Loading............
Kernel command line: run alarm-multiple
Pintos booting with**
Nothing is coming after pintos booting with
You are using an old version of pintos.
Use the latest version available here.
git://pintos-os.org/pintos-anon

Lose data of local MongoDB

My scenario is that I use a local DB and I always keep it running. An hour ago, I upgraded iTerm2 and all opened windows/tabs closed. After I restart iTerm2, I found that mongod is still running, so I use kill $(pidof mongod) and restart with mongod --dbpath ./db. However, most data I inserted has disappeared. I have checked .zsh_history to confirm that I am using the same db folder. I have also checked all mongod.lock address on my computer to see other DB folders, and none of them stores my latest data. I have seen mongo.log and the commands I used to query new data was still there. Therefore, how can I find my lost data? Thanks.
P.S. This situation happened last month when my mac was forced to shut down because of low battery. It happens again so I ask and want to know why it happens and what I can do.

Postfix: fatal:unsupported map type for this operation: hash

I am trying to configure postfix on my Raspberry Pi (OS: Raspbian).
I get this Fatal Error Message when I try to execute following commands:
postmap
newaliases
Any idea?
For me, the cause was that Berkeley DB support is needed.
For the Raspberry Pi I don't see any option for Berkeley DB. After I installed postfix it just worked. I know this post is old, but in case it helps anyone: Perhaps re-installing postfix-lmdb or postfix-cdb would be the fix needed on a Pi.
For anyone using Gentoo Linux, add "mail-mta/postfix berkdb" to /etc/portage/package.use or a file inside that if it is a directory, then recompile postfix.

Can not stop postgres despite immediate stop

I have this issue that is driving me nuts. Despite all my efforts, I am not able to force my postgres server to shut down. I have followed those instructions : http://www.question-defense.com/2008/10/17/pg_ctl-server-does-not-shut-down-force-postgres-to-shutdown
but still, nothing happens and all I got in the shell is
waiting for server to shut down............................................................... failed
pg_ctl: server does not shut down
Any help much appreciated.
Update: Checking the logs, I have this recurring error :
LOG: checkpoints are occurring too frequently (25 seconds apart)
HINT: Consider increasing the configuration parameter "checkpoint_segments".
After giving it a lot of thoughts especially on the way I installed it at the first place, I realize that I set up the install so the daemon would launch postgres at the start of my machine. Thus, any manual killing would simply result in the recreation of those process by the same daemon.
To resolve this problem you need to stop the daemon from working using launchctl and remove a .plist file in your postgres directory.
Good luck if you face the same problem.
You probably run with the default setting of "checkpoint_segments = 3", that produces the warnings. Your database does many writes, right? It takes some time to write all of this to disk, and your database is quite busy rotating the logfiles, instead doing real work.
If you increase checkpint_segments, you will see performance improvements, and less I/O.
For further readings: https://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server