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Using Google and Bing in Systems Administration - A Brief Note.

Use both search engines Although Microsoft and Google claim that they do not alter search results to promote their interests, they do. It's not necessarily a bad tactic [1]. Just be aware of the behavior. General Steps If you have a general problem, troubleshoot until you have a specific issue/question. If you cannot figure out the answer, run it through both Google and Bing. If you get results, it's either known configuration problem or a known issue with your product. Hopefully there will be a solution. If you get no results, you can generally assume that you are making a common configuration mistake, the solution to which is considered so self-evident that user community of your product doesn't feel it's worth writing up. Re-read your manuals, guides, and tutorials. See the XKCD flowchart for a similar process for family IT problem resolution. No Results At All If you get no results on a specific issue search for a product that is specific to a par...
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How to fix this ssh error from a Cisco switch: ssh_rsa_verify: RSA modulus too small: 512 < minimum 768 bits

Problem ssh user@cisco_switch returns: ssh_rsa_verify: RSA modulus too small: 512 < minimum 768 bits key_verify failed for server_host_key Solution The modulus of the ssh RSA key pair on the switch is too small. If you have access, generate a new key pair on the switch with a larger modulus. Procedure Login with ssh protocol version 1 ( ssh space dash one ): ssh -1 user@cisco_switch (On the switch): enable (On the switch): Authenticate to "Privileged Exec Mode" mode on the switch. (On the switch): conf t (On the switch): crypto key generate rsa general-keys modulus 1024 (On the switch): Press enter to accept that the current key pair for the switch will be replaced. You now should be able to log into the switch with ssh protocol version 2.
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Lingo: Destructive Buy-in

Lingo: Destructive Buy-in Definition : Enough buy-in from employees and/or management to approve an idea or project, but not enough buy-in to execute it successfully. Origin: Corporate lore from a now-defunct biotech firm in MA, USA. First seen in an early Scott Adams interview in the form "destructive agreement".
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How do I find which package contains a certain file?

What to do if you need to install or build a package on Linux and it wants a missing file/library/etc... Have you ever tried to install package or some vendor software, only to find that the install fails due to a missing library? Here is a collection of methods for finding the package that contains the missing file. Red Hat Enterprise Linux/CentOS Using yum yum whatprovides /full/path/to/missing/filename Note: In all of these processes, fill in the actual filename and path for which you are looking. Using rpmfind site Browse to http://rpm.pbone.net/index.php3/stat/2/simple/2 Enter filename or /full/path/to/missing/filename in the search box (start with just the filename) Check boxes of rpm-based distributions in which you want to search Click search Debian/Ubuntu apt-file sudo aptitude install apt-file sudo apt-file update apt-file search filename or apt-file search /full/path/to/missing/filename Using Debian's website Browse to http://www.debia...
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Local-link Address (LLA, 169.254.0.0/16) networking on Debian/Ubuntu Linux How To

Instructions for connecting external IP devices to the second NIC on a Debian/Ubuntu box using Local-link Address networking (169.254.0.0/16) e.g. connecting a Axis 206M camera. Install on the Debian/Ubuntu PC: dhcp3-server avahi-autoipd To configure dhcpd, add the following lines to /etc/dhcp3/dhcpd.conf: subnet 169.254.0.0 netmask 255.255.0.0 { range 169.254.8.2 169.254.8.20; } Add a route to 255.255.255.255 to the second NIC in order to send UDP broadcast traffic to it. This is accomplished by the last two lines below in /etc/network/interfaces: % cat /etc/network/interfaces auto lo eth0 eth1 iface lo inet loopback address 127.0.0.1 netmask 255.0.0.0 iface eth0 inet dhcp iface eth1 inet dhcp post-up route add -net 255.255.255.255 netmask 255.255.255.255 metric 99 dev eth1 post-down route del -net 255.255.255.255 netmask 255.255.255.255 metric 99 dev eth1
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