Source IP Address Based on User

If you want to use different source IP addresses based on the logged in user or running service on a Linux computer you can use these simple commands: /sbin/ifconfig eth0:1 NEW-IP-ADDRESS netmask YOUR-NORMAL-NETMASK /sbin/iptables -t nat -A POSTROUTING -m owner –uid-owner USERNAME -j SNAT –to-source NEW-IP-ADDRESS You can use this if the source IP is …

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NVidia Driver on Linux-4.11.1

Problem: after installing linux kernel 4.11.1, the dkms package of the nvidia driver does not compile. You find some cryptic error message about ./Kbuild in  /var/lib/dkms/nvidia-current/375.39/build/make.log Solution: I uninstalled the debian nvidia package and installed the newer driver from the NVidia homepage: aptitude remove nvidia-installer-cleanup ./NVIDIA-Linux-x86_64-375.66.run After this upgrade nvidia and linux 4.11.1 works again Versions: before upgrade jessie …

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Firefox Audio is Broken due to PulseAudio Dependency

Problem: Firefox 52 audio does not work without pulseaudio. Discussion: pulseaudio is a bloated audio daemon that often fails. In the last years, when ever audio failed on linux, the quickest solution was to uninstall pulseaudio. But the Firefox developers made the mistake to remove support for the underlying audio driver alsa, and insist on the middle …

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Check Raid Status for Dell Raids on Linux

Linux support from dell is still very poor. They still support only RedHat$ and SuSE$. But there are ways to check the Raid status of Dell server on debian. http://hwraid.le-vert.net/ is doing a good job in collecting information and building Debian style packages. Example:  A Dell server “PowerEdge T130” with “LSI Logic / Symbios Logic MegaRAID SAS-3 …

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Cups PDF Filter Crashes

Problem: for some PDF files cups does not print the page, the web gui just tells “filter failed” and in the cups logfile you find [Job 528] PID 19521 (gs) crashed on signal 11! Discussion: cups on debian uses ghostscript as pdf renderer. The pdf renderer of ghostsciprt crashes on many files. You can test by simply running …

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Rare Connection Resets after Linux Upgrade

Problem: after upgrading from Debian 6 to Debian 8 some of the machines lose their ethernet network connection under heavy load for some seconds rarely. You find lines like these in syslog: [2333099.217735] NETDEV WATCHDOG: eth1 (tg3): transmit queue 0 timed out [2333099.217966] tg3 0000:03:04.1 eth1: transmit timed out, resetting [2333099.384391] tg3 0000:03:04.1 eth1: 0: Host …

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Compiling Sendmail on Debian7

Problem: after compiling sendmail on Debian7 with “./Build” sendmail does not recognize hash .db files. You see the following error message: readcf: map access: class hash not available Discussion: ./Build should detect the berkley DB automatically. When devtools/bin/configure.sh finds libdb.so it adds -DNEWDB as compile option. On Debian7 the libdb.so file moved to /usr/lib/x86_64-linux-gnu/ and configure.sh fails to …

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