Welcome to Catalin(ux) M. BOIE's page!
Here you can find some work of mine on Linux kernel & other stuff.

E-mail: catab # embedromix dot ro
Phone: +40-745-048374
RSS feed for this site
IPv6 Ready
My Fedora repository: rpm -Uhv http://kernel.embedromix.ro/dinorepo-0.0.11-1.noarch.rpm
My Oracle/RedHat/CentOS repository: rpm -Uhv http://kernel.embedromix.ro/dinorepo-el-0.0.12-1.noarch.rpm
Supported architectures: x86_64, i386, armv7hl, aarch64.
For commercial support and customizations, contact us at: Embedromix

[Home]  [Networking]  [Crypto]  [Linux kernel patches]  [Userspace]  [Docs]  [CV/Resume]  [Links

Name Description Links
IFB A mini howto on how to shape on incoming packets and distribute packets on multiple interfaces, sharing bandwidth. ifb.html
RAID mini HOWTO A mini howto describing linear, 0, 1, 5 and 6, using mdadm. RAID.html
git mini HOWTO A mini howto describing how to use git. git.html
LVM mini HOWTO A mini howto describing how to use LVM. LVM.html
IPv6 mini howtos Some mini howtos to easy IPv6 implementation. ipv6.html
Random stuff Some usefull one-liners. random.html

Random stuff

  • Limit number of connections per second for ssh to maximum of 4 in 60 seconds:
    iptables -I INPUT -p tcp --dport 22 -i eth0 -m state --state NEW -m recent --set
    iptables -I INPUT -p tcp --dport 22 -i eth0 -m state --state NEW -m recent --update --seconds 60 --hitcount 4 -j DROP
    
  • Typing Unicode characters: CTRL+SHIFT+u, then the numeric code.
  • Making an SELinux domain permissive: /usr/sbin/semanage permissive -a httpd_t
  • Disabling HPA at boot (BIG WARNING: YOU CAN LOOSE DATA!): libata.ignore_hpa=1
  • Disabling HPA per disk (BIG WARNING: YOU CAN LOOSE DATA!): hdparm -N p<number_of_sectors> /dev/sd?
  • SELinux on low memory: /etc/selinux/semanage.conf: bzip-blocksize=4 and bzip-small=true
  • PostgreSQL: Find unused indexes: SELECT schemaname, relname, indexrelname, idx_scan, idx_tup_read, idx_tup_fetch FROM pg_stat_user_indexes;
  • PostgreSQL: Show activity: SELECT * FROM pg_stat_activity WHERE current_query != '<IDLE>';
  • Convert to ext4: tune2fs -O extents,uninit_bg,dir_index /dev/sdaaaa
  • Screencast: ffmpeg -f x11grab -g 250 -s 1024x768 -r 25 -y -sameq -i :0.0+0,0 x.avi.
  • Screencast (mkv): ffmpeg -f x11grab -g 250 -s 1024x768 -r 30 -y -sameq -i :0.0+0,0 -vcodec libx264 -vpre lossless_ultrafast -threads 0 x.mkv.
  • Keyboard fast rate: xset r rate 150 40
  • Dinamically grow a disk online under KVM/libvirt:
    Find devices: virsh domblklist NAME_OF_THE_MACHINE
    Resize: virsh blockresize NAME_OF_THE_MACHINE vda 12G
    'vda' may need to be replaced with something else.
    The size must be the final size! Do not shrink!