NIST ion clock sets new record for most accurate clock 1 year ago
I wonder if they'd consider implementing NTS.
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mccoyc
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Chris is a principal engineer in Cisco's Advanced Security Initiatives Group (ASIG) and published author.
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It's probably a lot of automated tooling/monitoring infrastructure that's doing reverse resolution of IPs to get hostnames.
Edit: I've found that sometimes they're pretty poor at caching responses so you end up with a lot of these requests.
GCP Outage 1 year ago
Can confirm us-east1 (and possibly us-south1) are having VPC host reachability problems.
Traceroute works by observing Internet Control Message Protocol (ICMP) time to live/hop count exceeded messages and noting the source IP of those messages. There's plenty of resources you can search on to learn more about this. When you see * * *, it means that for that given TTL value, no corresponding ICMP messages were returned to the source.
It could be because they were filtered at the boundary of the network. If source IPs are private (RFC-1918 or carrier grade NAT space), those ICMP messages should get dropped. This is Best Current Practice (BCP) 38, if you wanted to read more about it.
Ever want to know why IPv6 is so important? This is another reason why. Troubleshooting networks without globally significant IP addresses on the intermediate hops is a real pain.
Yes! RF is fun for hackers. Go get licensed. 73 de KQ4RLZ.
Agreed. 48V (actually -48V) has been used across telco central offices for decades.
It works, but anytime you have custom networking or more complex cloud-init configs, you'll have to go into "snippets" territory or referring to files in a local filesystem of the host. They don't have API support for making snippets the last time I checked. Where I ran into this was when trying to set up hosts with Terraform on Proxmox VE (which works well itself too).
I agree. It absolutely is IPv4. Hosts could use DHCPv6 with prefix delegation (DHCPv6-PD), and use that delegated /64 for its internal Docker bridge and get rid of NAT. And yes, you can still have your Netfilters stateful packet filtering in place! People are going through so much pain because they won't embrace the tools IPv6 gives you! This solution is 20 years old. God help you if your network is actually using 172.17.0.0/16. grumble grumble get off my lawn, kids.
Touch Pianist 3 years ago
The first movement is one of the only pieces I can play on the piano. Yes indeed, anyone can learn it! I came from a musical family, but never really put the effort into learning the piano.
I'm not sure where I heard this, but Beethoven wrote this for one of his students that he was in love with. The first movement was purposefully written for a newcomer to be able to play--such as for whom he admired, but the third movement was a representation of his anger over being rejected, and is one of the hardest piano pieces to play.
Cisco's SiliconOne is programmable using P4 as well. I'd be curious to know if it'd work for your use cases. It certainly isn't going anywhere since we're using it in darn near all our products now.
Disclaimer: I work for Cisco.
Ansible Techniques I Wish I’d Known Earlier 5 years ago
Another one for the list is `--start-at-task` and `--list-tasks`, for those tasks that are statically imported. If you have a task bomb out, you can take over from where you left off. Doesn't work in all playbooks, if facts need to be set earlier, but it's still very useful and saves tons of time. Obvious, but I wish I knew that one earlier too.