SSL certs

Nginx

cat mysite.crt gd_bundle.crt > mysite_combined.crt

thanks to: http://nginx.groups.wuyasea.com/articles/how-to-setup-godaddy-ssl-certificate-on-nginx/2

Tomcat 7

openssl pkcs12 -export -in mycert.crt -inkey <mykey.key> -out <mycert.p12> -name tomcat -CAfile <Entrust_SSL_CA.cer> -caname root -chain


Where:

• <mykey.key> is your current private key.
• <mycert.p12> is your current openssl certificate
• <Entrust_SSL_CA.cer> is the Entrust Secure Server Root CA available for download at the following URL https://www.entrust.net/downloads/root_index.cfm

The exported keystore will be in <mycert.p12>

thanks to: http://www.entrust.net/knowledge-base/technote.cfm?tn=6557

 

UTF-8 in python

These Slides are the answer!!!

Multiple Ucarp on the same host

Thanks to this Guy!

http://ajohnstone.com/achives/running-several-vips-on-the-same-interface-with-ucarp-and-haproxy/

Ruby web app: what are the chances?

Fantastic discussion from a Passenger Developer here

 

How to draw flow and chart in ASCII

This is a very nice online tool:

http://www.asciiflow.com

 

SSH tunnel to cross ugly firewall

ssh -L localport:remoteip:serviceport username@remoteip
In this way we can access the service running on remoteip on the port serviceport (a working account on remoteip is needed)

FFmpeg: Dump audio in mp3

Sometimes is useful to dump the audio stream from a a/v file recompressing it into a mp3.

ffmpeg -i $input.avi -vn -ac 1 -f mp3 -acodec libmp3lame -q 9 $output.mp3


 

• -i: specify the input file
• -vn: ignore the video stream
• -ac:numver of  audio channels in the output file
• -f: output file format
• -acodec: audio codec
• -q: audio quality (1 best – 9 worst)

 

Shrink large PDF files

To shrink a PDF file (without pictures) you can try:

gs -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=setting -sOutputFile=output.pdf input.pdf

where setting should be replaced by

• screen
• ebook
• printer
• prepress

 

thanks to: http://www.ehow.com/how_6823473_reduce-pdf-file-size-linux.html

 

How to update Nokia 5530 Express Music in VirtualBox

The sole interesting issue is:

create a filter to auto attach the device to the vm using only the vendor id

Thanks to:

http://tumble.mlcastle.net/post/17703937464/updating-nokia-phones-with-virtualbox

How to map ataX to sdY

When disks start to crash, the kernel try to warn the sysadmin with, not so readable, messages.

[12270071.931301] ata1.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0
[12270071.931421] ata1.00: irq_stat 0x40000008
[12270071.931524] ata1.00: failed command: WRITE FPDMA QUEUED
[12270071.931634] ata1.00: cmd 61/02:00:67:99:07/00:00:00:00:00/40 tag 0 ncq 1024 out
[12270071.931635] res 41/10:01:67:99:07/00:00:00:00:00/40 Emask 0x481 (invalid argument) <F>
[12270071.931918] ata1.00: status: { DRDY ERR }
[12270071.932021] ata1.00: error: { IDNF }
[12270071.934760] ata1.00: configured for UDMA/133
[12270071.934775] ata1: EH complete

How can i understand what device should be replaced ?

This script can help.

fail=1 ; a=`egrep "^[0-9]{1,}" /sys/class/scsi_host/host*/unique_id | grep ":$fail" | cut -d "/" -f 5` ;  ls -l /sys/block/sd* | grep $a | rev | cut -d "/" -f 1 | rev