~/blog

Tag: networking

  • Configuring NAT66 on ScreenOS

    I recently had to deploy redeploy an old NetScreen 5GT to segregate a production LAN and create a small lab network. The production LAN has a routable IPv6 /64 prefix, delivered via a Hurricane Electric IPv6 tunnel. The lab network also required IPv6 connectivity. We also recently obtained a /48 prefix from Hurricane Electric, so…

  • Exporting a X.509 certificate public key from Junos

    I’ve just spent the last couple of hours trying to find a way to export the public key from a locally generated, self-signed X.509 certificate on a Juniper SRX-100 firewall. Apparently there is no Junos CLI command to do this, so after poking around the filesystem from a shell on the box, I found the…

  • Cisco Wireless LAN Controllers and DHCP Option 43

    I recently had to install a Cisco Wireless LAN Controller (2112, if you’re interested), and had the usual fun and games with getting it to properly understand DHCP Option 43. For the uninitiated, option 43 is a vendor specific option, which, in the case of Cisco WLCs, is/are the manager IP address(es) of controllers that…

  • The Amazing Unmanaged Trunk Mode Switch

    Have you ever needed to set up a bunch of equipment on a boardroom table or some other temporary location, and needed both native and 802.1q tagged VLANs, but only had one available switchport? A quick n’ dirty solution is to use an unmanaged switch, such as one of the numerous 8-port desktop switches from…

  • Cisco 857 router

    I’ve finally replaced my trusty old D-Link DSL500, which I’ve had for about four years, with a Cisco 857. What can I say about these routers… well… My 857 router arrived with SDM Express, but not SDM, installed on the flash drive. While SDM Express is an improvement over the old Cisco Router Web Setup…

  • Catalyst Express(?!) 500 switches

    On the weekend I helped a friend set up some Cisco kit involving Catalyst Express 500 switches, Aironet 1310 wireless bridges, and various Cisco IP phones. What should have been a relatively simple job ended up taking about 10 hours. My friend had already configured the 2800 series router, with Cisco Call Manager Express. Phones…