Tag Archives: Windows

Basic IPv6 Messages (v2): Wireshark Captures

IPv6, Memorandum, , , , , , , , , , ,

In my IPv6 classes, I always teach the basic IPv6 messages as seen on the wire. There’s so much new stuff, such as Router Advertisements, Duplicate Address Detections, Neighbour Solicitations, and so on. Therefore, I’m using a rather simple packet capture showing the starting process of a client getting its addresses.

For the last 10 years, I used this capture, which I took on a Knoppix Linux along with a German Speedport router, in which SLAAC was used for getting the addresses. However, it turned out that in enterprise-grade networks, stateful DHCPv6 is used more commonly. Hence, I did it again and captured the very first IPv6 messages as seen on an IPv6 node, but this time on a Windows 11 PC and a Debian 13, along with stateful DHCPv6.

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Basic NTP Client Test on Windows: w32tm

Monitoring, NTP, Windows, , , ,

When implementing NTP servers, it’s always an interesting part to check whether the server is “up and running” and reachable from the clients. While I’ve done many basic NTP checks out of Linux, I lacked a small docu to do this with Windows. It turned out that there’s no need for third-party software because Windows already includes a tool to test NTP connections: w32tm.

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PAN NGFW IPv6 NDP RA RDNSS & DNSSL

DNS/DNSSEC, IPv6, Palo Alto Networks, , , , , , , , , ,

Haha, do you like acronyms as much as I do? This article is about the feature from Palo Alto Networks’ Next-Generation Firewall for Internet Protocol version 6 Neighbor Discovery Protocol Router Advertisements with Recursive Domain Name System Server and Domain Name System Search List options. ;) I am showing how to use it and how Windows and Linux react to it.

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Software Updates korrekt installieren

Windows, , , , , ,

Bei Privatpersonen sehe ich es sehr oft, dass Software Updates bei ihren Windows Computern nicht installiert werden. Entweder sie werden komplett ausgelassen oder zumindest erst nach einigen Wochen installiert. Dabei ist es ziemlich wichtig dies zeitnah zu tun, da die Hersteller durch Updates unter anderem Schwachstellen/Sicherheitslücken in ihren Produkten ausbessern. Und obwohl das Installieren solcher Updates eigentlich nicht schwer sein sollte, sind manche Einstellungen während der Installation irreführend. Außerdem werden einem teilweise weitere Kuckucks-Softwares untergejubelt, die man eigentlich gar nicht möchte. Deswegen stelle ich hier ein paar Screenshots zur Verfügung, um die Installationen der bekanntesten Updates “richtig” durchzuführen.

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Windows 7 IPv6 Neighbor Cache Bug?

IPv6, Security, , ,

Last year, I posted the following bug report on the IPv6 hackers mailing list, but nobody ever responded. I also sent it to Microsoft, but heart no response either. Since I am owning this blog since a few days, I will post it here, too:

Hello everybody,

I am testing with the THC-IPV6 Toolkit from van Hauser and noticed that Windows 7 adds and deletes several neighbor cache entries even on interfaces which are not connected. It further adds and deletes complete network interface cards from the neighbor cache. I would like to know if this is a feature or a bug.

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