====== OpenWRT tipy, finty ======

===== nastaveni time zone =====
<code>
echo "CET-1CEST-2,M3.5.0/02:00:00,M10.5.0/03:00:00" > /etc/TZ
</code>
http://wiki.openwrt.org/oldwiki/openwrtdocs/whiterussian/configuration

===== statistiky provozu =====
  * jak nahradit hotsanic? :) - pomoci iptables :-D

<code>
root@HomeRouterII:~# iptables -L INPUT -vxn
Chain INPUT (policy ACCEPT 8444 packets, 1003147 bytes)
    pkts     bytes target      prot opt  in      out       source               destination         
 1828997 189743951 ACCEPT      all  --    *        *       0.0.0.0/0            0.0.0.0/0           state RELATED,ESTABLISHED 
   30524   1893399 ACCEPT      all  --   lo        *       0.0.0.0/0            0.0.0.0/0           
   10019    529628 syn_flood   tcp  --    *        *       0.0.0.0/0            0.0.0.0/0           tcp flags:0x17/0x02 
 2153813 265801766 input_rule  all  --    *        *       0.0.0.0/0            0.0.0.0/0           
 2153766 265799194 input       all  --    *        *       0.0.0.0/0            0.0.0.0/0    
</code>

  * pomoci -z lze zresetovat statistiky
  * http://open-wrt.ru/forum/viewtopic.php?id=5242
  * pokud nebude moc big.. lze pouzit rrdtool
  * http://www.root.cz/clanky/prechadzame-na-rrdtool/
  * mozna neni vubec potreba perl.. proc? 
  * tutorial na rrdtool nepouziva perl :) http://oss.oetiker.ch/rrdtool/tut/rrdtutorial.en.html
  * neci pokus a jednoduchy statistiky.. ale s perlem :) http://sandbox.cz/~covex/czfree/rrstats.html
  * zavislosti u openwrt rrdtool (74066) -> librrd (655035) -> libart (97986), libfreetype (486683), libpng (296830), zlib (80048)
  * velikost potrebna pro rrdtool: ~ 1.7MB

==== iftop ====
  * kolik zabere? :)
  * iftop (62791), libpcap (180563), libncurses (425516), libpthread (83890)
  * celkem ~ 800K

===== Generovani NetFlow na embedded zarizeni =====
  * zkousel jsem generovat NetFlow pomoci fprobe/nprobe na mem RSpro .. pri 4Mbit to zralo asi 30% fprobe a 60% nprobe CPU, pamet minimalne
  * dnes jsem videl v akci router board 750 GL s Atheros AR7242 400MHz a 64 MB RAM, CPU bylo kolem 20% pri nf9, rikaji tomu traffic-flow
  * fprobe ma nejaky special modul pro cteni paketu z jadra, ale neumi nf9 a pry obsahuje hodne chyb
  * nadeje vkladam do ipt-netflow projektu :) pry je hodne rychly :)

===== build konkretni vereze kernel =====
Tweak the LINUX_VERSION variable in target/linux/ar71xx/Makefile.
Supported Kernels are listed in include/kernel-version.mk 
  * https://forum.openwrt.org/viewtopic.php?pid=91808