About

Martin Klier

usn-it.de

Prepare IPtables for the Cisco VPN Client

Hi out there, installing the Cisco VPN Client 4.8.00 should be no problem (just run “vpninstall” with kernel headers installed). But running it from the notebook in an insecure environment needs a host firewall on the mobile device. I love setting the default policies of a chain to “DROP”! But the VPN Client communicates via […]

read more

How to create a self-signed OpenSSL certificate

Hi folx, if you want to create a self-signed certificate with OpenSSL (useful for encryption-only purposes, e.g. your own mailserver) just do the following: openssl req -x509 -nodes -days 365 -subj ‘/C=DE/ST=Bayern/L=Munich/CN=www.example.com’ -newkey rsa:2048 -keyout key4cert.pem -out cert.pem It means: “-nodes” makes the key unencrypted “-days” makes it valid for n days “-subj” provides your […]

read more

Lost, deleted or corrupted a voting disk (quorum) in Oracle RAC 10.2 ?

Hi Folx, whenever you lost, deleted or corrupted a quorum aka voting disk in Oracle Real Application Cluster (RAC) 10.2, you have three options: 1) Reinstall your Clusterware, see Metalink Note 279793.1 2) Replay a backup taken with “dd if=/dev/votingdisk of=/backup/votingfile bs=4k” 3) Have a look at Metalink Note 399482.1 and the RAC Administration and […]

read more

How to move or add a controlfile when ASM is involved

Hi folx, sometimes, you may want to add or move a controlfile. On OS file system, this is no problem. Just “shutdown immediate”, change the CONTROL_FILES init parameter, copy or move the controlfile, and startup again. With ASM involved this is not possible, since the ASM does not allow direct move or copy commands. You […]

read more

Grid Control Agent install without Metalink Access

Hi folx, if you ever need to install Grid Control Agent 10g, there will be no option to avoid configuration of your Metalink Access Data. But you may want to avoid this. The trick is simple: Just decline the License Agreement in the middle of the runInstaller process. The function of agent will be installed, […]

read more

Asterisk at Usn’s

Hi, Asterisk PBX is a very smart telephone system for home, office and enterprise use. In December 2006 I had to decide between purchasing a new ISDN/analogous system for about 2 external ISDN- and 20 internal extension lines or trying something new, even cheaper. The Pros and Contras of Asterisk for me have been: […]

read more

Just another blog?

Hi folx, you may think: “Just another blog?” – and you may be right. But I had the intention to make notes about my IT work – why not publishing them? So this blog will provide hints and config snippets out of my daily life. I hope, here you can find what you are looking […]

read more