Added some further tips, Fixed typo in iperf tip

[grml-tips.git] / grml_tips

diff --git a/grml_tips b/grml_tips
index 0f72575..6067270 100644 (file)
--- a/grml_tips
+++ b/grml_tips
@@ -1088,7 +1088,7 @@ EOF
 See also: http://www.debian.org/releases/stable/i386/apcs04.html.en
 Avoid all of the above steps - use grml-debootstrap(8) instead!
 -- 
-Convert files from Unicode / UTF to ISO:
+Convert files from Unicode / UTF-8 to ISO:
 
 % iconv -f utf8 -t iso-8859-15 < utffile > isofile
 
@@ -2148,7 +2148,7 @@ Restore the backup using unzsplit:
 
 More usage examples: man zsplit + man unzsplit
 -- 
-Measure network performance using ipserf
+Measure network performance using iperf:
 
 Server side:
 % iperf -s -V
@@ -2500,7 +2500,11 @@ Configuration options relevant on harddisk installation:
   # tzconfig
 
   which adjusts /etc/timezone and /etc/localtime according
-  to the provided information.
+  to the provided information. Running:
+
+  # dpkg-reconfigure tzdata
+
+  might be useful as well.
 
 * /etc/default/rcS: set variable UTC according to your needs,
   whether your system clock is set to UTC (UTC='yes') or
@@ -2546,3 +2550,72 @@ Further information:
   http://www.debian.org/doc/manuals/system-administrator/ch-sysadmin-time.html
   http://wiki.debian.org/TimeZoneChanges
 -- 
+Recorder shellscript session using script:
+
+% script -t 2>~/upgrade.time -a ~/upgrade.script
+% scriptreplay ~/upgrade.time ~/upgrade.script
+-- 
+Test UTF-8 capabilities of terminal:
+
+wget http://melkor.dnp.fmph.uniba.sk/~garabik/debian-utf8/download/UTF-8-demo.txt.gz
+zcat UTF-8-demo.txt.gz
+
+or:
+
+wget http://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-test.txt
+cat UTF-8-test.txt
+-- 
+UTF-8 at grml / some general information regarding Unicde/UTF-8:
+
+  http://wiki.grml.org/doku.php?id=utf8
+-- 
+
+This allows one ssh connection attepmt per minute per source ip, with a initial
+burst of 10.  The available burst is like a counter which is initialised with
+10. Every connection attempt decrements the counter, and every minute where the
+connection limit of one per minute is not overstepped the counter is
+incremented by one.  If the burst counter is exhausted the real rate limit
+comes into play. This gives you 11 connectionattepmts in the first minute
+before blocked for 10minutes.  After 10 minutes block the game restarts.
+
+Hint: you could set the burst value to 5 and the block time to only 5 minutes
+to achive the same average connection rate but with halve the block time.
+
+iptables -A inet_in -p tcp --syn --dport 22 -m hashlimit --hashlimit-name ssh \
+         --hashlimit 1/minute \ --hashlimit-burst 10 --hashlimit-mode srcip   \
+         --hashlimit-htable-expire 600000 -j ACCEPT
+iptables -A inet_in -p tcp --dport 22 -m state --state NEW -j REJECT
+-- 
+Tunnel a specific connection via socat:
+
+On the client:
+% socat TCP4-LISTEN:8003 TCP4:gateway:500
+
+On the gateway:
+# socat TCP4-LISTEN:500,fork TCP4:target:$PORT
+
+Using localhost:8003 on the client uses the tunnel now.
+-- 
+Set date:
+
+# date --set=060916102007
+
+where the bits are month(2)/day(2)/hour(2)/minute(2)/year(4)
+
+Set date using a relative date:
+
+# date -s '+3 mins'
+
+or
+
+# date -s '+tomorrow'
+
+Display a specific relative date:
+
+# date -d '+5 days -2 hours'
+
+Don't forget to set hardware clock via:
+
+# hwlock -w
+-- 
+