Category: sysadmin

  • Quick SSH security tips

    Just a quick post about a page I stumbled across, and I merely want to keep it in bookmarks. I was talking to some people to secure public facing SSH servers; and while we have the obvious: Only allows SSH2 Disable root logins Use keypairs instead of passwords Implement fail2ban When researching to make internet…

  • Error mongoDB under Ubuntu – can’t find libmozjs.so

    When installing MongoDB under Ubuntu, one could stumble upon the following problem: mongo: error while loading shared libraries: libmozjs.so: cannot open shared object file: No such file or directory This is caused because MongoDB uses XulRunner for it’s operations. (This is also why you see a bunch of X11 programs that are to be installed…

  • How to shrink Microsoft SQL log files

    When having Microsoft SQL databases, its log files can grow quite a bit, potentially slow down the database server and eat up disk space. To shrink a database, one can run the following line: EXEC D_ShrinkDBLogs 0,100,1000,’with truncate_only’,’DB_NAME’ (change DB_NAME with the database’s name) To shrink all databases, one can use “sp_MSforeachdb” which is an…

  • Debian won’t boot on BL465 server

    When installing Debian on a HP BL465 server, we sometimes run into the problems that after installing, GRUB won’t boot up anymore. First off, it’s not a Debian specific problem, we had this problem with other Linux distributions also, but decided to standardize on Debian across the organization. Installing to the MBR fails, and you…

  • Reverse proxy for sharepoint on Linux using HAProxy

    At Nakheel, we needed to load balance a new sharepoint instance. Our new sharepoint is single sign on, and was running on 2 web servers which needed to be load balanced. We played around with Apache for a while, and it’s awesome proxy balancer, but it gave us the problem that it was always asking…

  • Changing NSClient++ configurations in bulk

    At work, we started using Nagios to monitor the hosts and their services for any issues, so we can, proactively, take actions when we see trouble coming (hard disk that fills up rapidly, restarting services, etc). Recently we change the Nagios host to another IP address and found ourselves having to change a few dozen…

  • Change the ILO server name under Linux

    At work, we have a lot of HP Blade servers, and manage these through HP Onboard Administrator. By default, the server names are adapted from the Windows hostname, due to HP Insight Management agent tools. When running Linux, there doesn’t seem to be a option, or at least I couldn’t find one. While questioned a…

  • Microsoft Virtual Server 2005 – network trouble?

    Hi all, In our intranet development environment we run Microsoft Virtual Server, it was setup by the consultants who developed our Intranet’s first phase. Now, the second phase is about the start, we dusted off those servers and found out that the virtual machines all had no network adapters installed anymore. After cursing, and making…

  • nnscfgmaker.sh: a nagios/nsclient++ cfg maker

    Dear all, We are in the process of changing the monitoring system on part of our network from Zenoss to Nagios. This is not a Zenoss vs. Nagios debate, as both products are awesome and do the things they are designed for very well. We (Christian and myself) use a combination of Cacti for bandwith…

  • Tar based incremental backups

    A small bash script I wrote to have incremental backups done on a unix server, and then pushed to a Windows File system. On the fileserver, we add this directory to the normal backup. This is on a mail server, where emails are stored in MailDir format. We create weekly full backups on sunday, and…