The tag has no usage guidance.

learn more… | top users | synonyms

13
votes
4answers
596 views

dd: multiple input files

I need to concatenate chunks from two files: if I needed concatenate whole files, I could simply do cat file1 file2 > output But I need to skip first 1MB from the first file, and I only want ...
2
votes
1answer
33 views

Create table with frequency of unique names retrieved from multiple .csv files

I have 32 CSV files containing fetched information from a database. I need to make a frequency table in TSV/CSV format, where the names of the rows are the name of each file, and the names of the ...
0
votes
1answer
32 views

gzip - is there a risk to lose files during compression if process dead?

Is there a risk of losing files during compression if process dies? I'm gzipping big files using wildcard, but accidentally running it without screen or nohup. Is there a risk to lose source files if ...
-2
votes
1answer
20 views

How to migrate from one email provider to another? [closed]

I've used my own domain with the email service of yandex.com. Now I want to migrate to another email service provider. I've chosen zoho. 1) How can I copy all my email from yandex to zoho? Or ...
-1
votes
1answer
42 views

In a text file how can I sed multiple portions of text bordered by specific text patterns of text on Unix?

I use sed -n START_LINE,FINISH_LINEp filename > newfile to extract a specified range of text from a text file, e.g. sed -n 45,50p datafile > newfile. How can I use this to extract multiple ...
1
vote
1answer
56 views

md5 hash only first 512 bytes of file

Background I am about to migrate files from my old NAS to a new one, and want to verify the data integrity. The old NAS (Debian) is using Linux Ext3 file system, whilst the new one (FreeNAS) is based ...
2
votes
3answers
47 views

Copy column with file name as column header

I wanted to organize my dataset by copying the a column from a number of text file and append the file name in the first row of the new files. Here is sample of my data file1 a a b b 1 2 ...
0
votes
2answers
34 views

How to change the first column of data in a file?

I have .data file containing a table of numbers with the column format: m x y z vx vy vz separated by tabs, with a depth of 2000. The file name is initc.data. I want to change ...
0
votes
0answers
92 views

Nginx Performance Monitoring: How to collect CPU, Memory and Disk Utilization data?

I'm relatively new to shell programming and I need to collect statistical data on nginx web server performance running on Linux VMs for further analysis. I have checked some tools and I find dstat ...
0
votes
1answer
52 views

How to generate a Data URI from an image file?

There are online tools like duri.me that allow to create a Data URI from an image file. Are there any tools that run locally on Linux to do the same?
2
votes
3answers
657 views

To secure my data, is it good to have separate data partition (along with separate home partition)

I am installing fresh Ubuntu 15.10 on my laptop after erasing my hard disk completely. Now, what I am interested to know is whether it is good to have a separate data partition along with separate ...
1
vote
1answer
98 views

I've wiped my partition table using gparted and testdisk did nothing

I've wiped my NTFS partition table using gparted by clicking on "Device->Create Partition Table... and then apply" by accident. In this topic "I've wiped my partition table using gparted, is ...
0
votes
1answer
125 views

Which components are using virtual addresses, linear addresses, physical addresses and logical addresses?

I'm a bit confused about the different types of addresses in an operating system: virtual addressesare entirely used from the CPU ? physical addressesare used from what kind of hardware? linear ...
0
votes
0answers
11 views

Can suspending lead to data loss on an external HDD?

Let's assume we have an external HDD using an ext4 filesystem, powered via USB. Some write is ordered on the external drive, not synced yet. Then the user wants to suspend the system. Provided no ...
1
vote
1answer
49 views

add pairwise values looking up from a file

I have several variables (col1) which have 3 values (col 3,4,5) for some levels (col2) mango123 L1 1 2 3 mango123 L2 4 5 6 squash378 L1 7 8 9 squash378 L5 10 12 13 squash378 L15 0 1 3 ...
0
votes
1answer
270 views

Commands for data manipulation of binary to octave/hex formats?

I need to convert binary data to hex/octave/any suitable format and back to binary when I am splitting one big 1GB file into files containing 777 events each which are not of the same size such that ...
1
vote
3answers
53 views

Order of text jumbled when printing

We run an automated process which changes the data structure in a file, and it has run for about a year without any issues. It has just started failing and I have narrowed the problem down to one of ...
1
vote
3answers
292 views

Put big data of heterogenous byte offset into arrays by AWK

Assume the data consists of byte offset which is not fixed i.e. the distance of two subsequent file headers varies. The point of this thread is to go through each size of events separately in arrays. ...
1
vote
0answers
26 views

Pipe gzip output to Bluetooth transfer?

How do I pipe gzip output to Bluetooth transfer? I am able to send send file over Bluetooth using this command: bluetooth-sendto --device=12:23:35:96:45:45 file.tar However, piping gzip didn't ...
0
votes
0answers
56 views

Run Loop between starttime and endtime and get data from url

I want to check two conduction and run a loop for every one minute. There should be three variable start_time, end_time and current_time Conduction's: start_time should be greater than ...
0
votes
1answer
264 views

Deleting partitions without losing data

Case 1: Let's say I mount /dev/sda3 /var and this entry is not in /etc/fstab. After unmounting /var, if /dev/sda3 is an unused partition (no entries in the fstab), if I delete it I will not lose any ...
0
votes
0answers
69 views

Conceptual question about data corruption and mounting

If we have a partition /dev/sda1, and mount it to a mount point (i.e. /mnt), we can then use the files and folders under /mnt. Before changing the partition /dev/sda1 I umount /mnt, and then perform ...
2
votes
1answer
266 views

How to recover a shell script I deleted from a specific folder in Debian 7?

So in a merry mood last night, I deleted an important shell script from my system. I mistook it for something else and figured it wasn't needed. I am trying to recover it. I have tried 'scalpel' and ...
0
votes
1answer
264 views

Open Source Web Form Builder With Save to Spreadsheet or Database

Does anyone know of any open source tools that do essentially what Google Forms does. My company decided I could not use google forms because they did not want their info in the cloud, but for the ...
-1
votes
1answer
79 views

Erratic behavior with gzip on unix

I am compressing log files daily and very recently I have been seeing some crazy results on the file type of the file after compression. Normally you would expect file filename.gz returning gzip ...
1
vote
2answers
324 views

How can I remove a carriage return, add a time stamp and ignore some data from a live MQTT feed

I type mosquitto_sub -d -t +/# from the Ubuntu terminal to access the MQTT stream. Real output from the live MQTT stream is this: Sending PINGREQ Received PINGRESP Sending PINGREQ Received PINGRESP ...
1
vote
1answer
355 views

How to extract certain data from an MQTT stream

I type mosquitto_sub -d -t +/# from the Ubuntu terminal to access the MQTT stream. However I would like to see only a specific set of data from the MQTT stream. I've added | grep -v PING so ...
1
vote
2answers
47 views

MBR and data on pendrive

I have a pendrive (/dev/sdd). I ran fdisk -l and that shows me the drive and its partitions. After that I did: dd if=/dev/zero of=/dev/sdd bs=512 count=1 I deleted the MBR (so the partitions ...
3
votes
2answers
4k views

Use curl to send binary file through POST with content-type multipart/form-data;

A post request is made to: http://www.example.com/example/ and the post data is as follows: ------WebKitFormBoundaryB8NNdk2kNdndnnn Content-Disposition: form-data; name="picture[uploaded_data]"; ...
0
votes
1answer
566 views

using CURL to transmit binary data over POST parameter

How can i use CURL to send binary data through a specific post parameter? E.g in: curl 'http://www.example.com' -H 'hi:hi' --data ...
1
vote
2answers
164 views

Remove a line if regex exists only in 1st column of each line in a csv file

I have the following comma-delimited data (spaces used for visual clarity): 1 2014 23 2352 19.24 7.18 1 2014 23 2353 19.78 4.65 24 2014 23 2354 20.26 25.34 1 2014 23 2355 26.65 42.76 1 2014 23 ...
0
votes
1answer
44 views

Panic fault when mounting LVM2 volume

I have a CentOS 7 system that I can boot using a live cd. The system HDD's have an lvm2 partition with 2 volumes /root and /home. I can mount /root volume without any problems in the live ...
0
votes
1answer
1k views

Is there a standalone tool which will write reports from CSV data files

I download CSV files (e.g. my bank account transactions) and would like to build reports (to print) from the data. I have searched and found several report writer libraries, but all would force me to ...
2
votes
1answer
60 views

Ways to store data for command line API

I am developing an API in Unix environment for virtual machines. I have to store some information in a table about virtual machines. Currently I am using python dictionary of virtual machine objects ...
3
votes
2answers
557 views

Script using “split” in a loop over large files

I'm attempting to get a bash script working, and running into terrible errors along the way. The aim of the script is to break several large text files, into multiple files with a line count read from ...
2
votes
1answer
170 views

LibreOffice Calc Didn't Read Data with a formula (Error?)

So I have a data like this : (First Number) (=RIGHT(A1, 3)) 19132 132 56112 112 So, the second column formula is =RIGHT(A1,3) and so on. When I created the graph, it's show zero data, there are no ...
4
votes
6answers
21k views

NFS Automatic Fail-over or Load-balanced or Clustering?

I've been using NFS (and it is the only one i know well in Network Files) for a few years. But still can not able to find out .. How to make NFS Servers in Clustered Design (or Load-balanced?) Or at ...
-4
votes
2answers
124 views

What is the utility of piping to `/dev/null`?

Seeing that /dev/null's utility isn't immediately obvious to me, what is the use of /dev/null piping?
0
votes
0answers
25 views

Recover directory structure + files [duplicate]

Background: I had a dual boot of Windows + Linux Mint. Mint didn't feel right to me, so I decided to install Ubuntu to replace Mint. I booted from a Ubuntu Live USB and started the installer. The ...
0
votes
0answers
40 views

Replication data in SAN

I am using openfiler as SAN. Then I create a disk in SAN using ISCSI. I have 2 CentOS client machines connect to SAN disk. When I create data in client1 machine, It doesn't update to client2 ...
1
vote
0answers
47 views

Send big data with dsmigratedata command

I want send data to remote server using this command but I dont know what is the syntax is that I can use for this command... I'm using the command: $ dsmigratedate -s user@remoteip -p 22 password ...
2
votes
3answers
634 views

How to calculate the average value (per column) of the data that have the same ID in the first column?

I want to calculate the average value of my data when they have the same ID in the first column. I want to calculate the average values for the remaining columns that have the same value in the first ...
8
votes
3answers
482 views

Personal health records software

Does anybody know personal health records software for Linux? I want to record blood pressure, pulse, temperature, feel to analyze later. I will write information manually, as my measuring ...
3
votes
1answer
669 views

Can zfs resilvering destroy data with misreported device failures?

I have had a situation where I am moving data into a new zfs raidz pool with four devices, some of them virtual to facilitate the migration. The system completely hung in the middle of a device ...
1
vote
1answer
96 views

how to look the value of thedata by lookup index? [duplicate]

I have list of data array which I want to look the values by its index (id) and store to the index id from the data array. I can do it in spreadsheet VALUE LOOKUP function, but I still have lots of ...
1
vote
2answers
577 views

how to multiply column of one file by column of anothe file?

I want your help in multiplying columns of one file by column of other another file where both files have the same number of columns and rows. I want the script to multiply the first column of the ...
1
vote
3answers
2k views

Recover Windows partition in a GPT disk (previously MBR)

I have tried installing Arch Linux and what I ended up with was a partition scheme like this: /dev/sda: /dev/sda1 NTFS partition (Windows 7) /dev/sda2 ext4 (Arch) /dev/sda3 swap I don't know ...
3
votes
1answer
740 views

What are potential consequences of going nuts with sparse file based vdevs for a LVM to ZFS migration?

I've been playing around with ZFS having finally accepted that it's mature enough I shouldn't get burned. Now to migrate the home NAS box which is currently an LVM JBOD set up that's quite full, but ...
11
votes
3answers
37k views

How to mount a disk from destroyed raid system?

I have a horrible situation where I have to restore data from damaged raid system in a rescue Debian Linux. I just want to mount them all to /mnt/rescue in read only modus to be able to copy VMWare ...
1
vote
1answer
905 views

Is there a way to store mail attachments outside of mailboxes?

Nowadays, size limits on mail attachments are less comprehensible by traditional users. I am looking for a way to extract mail attachments as simple files that I would be able to manage elsewhere. On ...