Recent posts (paged)
Unix/Linux date command fails when calculating "yesterday"
Problem: A shell-script running every day short after midnight doesn't work properly once per year after daylight-saving time adjustment. e.g. an expected logfile is missing ("somefile.YYYYMMDD.log") Discussion: The Unix date command calculates the wrong date when used with "--date yesterday" on the day after daylig...
Openbox Config File
I don't use desktop environments on Linux. I prefer small,fast, efficient window managers. Some years ago I used olvwm (open look window manager) which was dicontinued by sun. Then I switched to wmx which I patched for my needs, but still it was missing some features. Now I use openbox which is highly configureable ...
Copy'n'Paste from Xterm to Chrome
Problem: X11 has a classical copy/paste mechanism which is: select text - press middle mouse button in the target field. And there is a second copy/paste which was adopted from Mac and Windows which is: select text - Ctrl-C - click into tagert field - Ctrl-V. I prefer the classical approch, but in some web applicati...
Cisco ASR 1002-X and PPTP
Problem: PPTP from any client to an ASR1002-X Cisco does not work. PPTP Connections starts but in PPP LCP phase the connection fails. Solution: Cisco ASR1002-X with Software IOS-XE 15.3(2)S2 has no PPTP support. You have to take a different Router! Discussion: The weird thing is, that most of the PPTP stack is still...
Ping to Windows Server 2012 with Direct Access fails
Problem: Ping from Linux computers to Windows Server 2012 with Direct Access fails for hours (no response) although connectivity is working (eg. HTTPS) Discussion: Ping from other windows machines and Cisco machines worked, but from Linux machines ping was not answered. I tried to find the difference between those I...
Hide Mouse Coursor on X11/Xorg
Problem: for some applications a mouse coursor in disturbing. E.g. video players, signage display. Solution: the tool unclutter hides the mouse coursor after a chosen idle timeout. Unclutter is part of the main debian repository. Version: Debian 7.1
Clamav/Freshclam update fails!
Problem: I got the following error message in the the freshclam.log file on several servers with clamav installed. ERROR: getpatch: Can't download daily-16682.cdiff from database.clamav.net Due to this bug the virus database wasn't updated for days! It seams to be a bug in clamav with dialy-16682.cdiff (dialy.cvd in...
Linux on HP servers
Problem: You want to check the hardware health status on you debian server running on an HP ProLiant hardware. After spending some time on the HP.com homepage, I got really angry. HP does a really bad job on their support homepage. If you search for DL360 G5 you see a list of operating systems. The list of Debian OS...
CDP / LLDP Fun
Problem: You want to know which switch and what port your Linux machine is connected to? Solution: If the switch does CDP (all Cisco switches do), it tells you a lot of information. Tcpdump can capture and show this information. # tcpdump -i eth0 -n -v -s 1500 -c 1 'ether[20:2] == 8192' tcpdump: listening on eth0, l...
AVM Fritz!box DHCP Problem
Problem: I wanted to provide a CWMP (TR-069) ACS URL to an AVM modem using DHCP on the WAN Interface, but the DHCP server ignores this vendor-option. Discussion: Following the TR-069 specs, the CWMP-ACS Server can be included in an dhcp response using vendor-option (SubOption 1). Usually vendor options should work w...