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Amazon Route 53 的 Auto Naming API 可以指到 CNAME 位置了

Amazon Route 53 的 Auto Naming API 可以拿來跑 Service Discovery (參考先前的「用 Amazon Route 53 做 Service Discovery」這篇),當時是 A/AAAA/SRV record,現在則可以註冊 CNAME 了:「Amazon Route 53 Auto Naming Announces Support for CNAME Record Type and Alias to ELB」。

最直接的影響就是 ELB 的部份了,透過 ELB 處理前端的話,覆載平衡以及數量限制的問題就會減輕很多 (之前是靠 Round-robin DNS 打散,而且限制一次最多回應五個 record):

Beginning today, you can use the Amazon Route 53 Auto Naming APIs to create CNAME records when you register instances of your microservices, and your microservices can discover the CNAMEs by querying DNS for the service name. Additionally, you can use the Amazon Route 53 Auto Naming APIs to create Route 53 alias records that route traffic to Amazon Elastic Load Balancers (ELBs).

兩個 gperf...


一個是 GNUgperf,給定字串集合,產生 C 或 C++ 的 perfect hash function (i.e. no collision):

GNU gperf is a perfect hash function generator. For a given list of strings, it produces a hash function and hash table, in form of C or C++ code, for looking up a value depending on the input string. The hash function is perfect, which means that the hash table has no collisions, and the hash table lookup needs a single string comparison only.

另外一個是 Google 弄出來的 gperftoolsmalloc() 的替代品以及效能分析工具:

gperftools is a collection of a high-performance multi-threaded malloc() implementation, plus some pretty nifty performance analysis tools.

用 Amazon Route 53 做 Service Discovery

Amazon Route 53 的新功能,可以解決以前自己要建立 Service Discovery 服務的工作:「Amazon Route 53 Releases Auto Naming API for Service Name Management and Discovery」。官方的文件在「Using Autonaming for Service Discovery」這邊。

不過目前有些限制,一個 namespace (domain name) 目前只能有五個服務:

DNS settings for up to five records.

然後 DNS 回應時,最多回八個 record:

When Amazon Route 53 receives a DNS query for the name of an instance, such as backend.example.com, it responds with up to eight IP addresses (for A or AAAA records) or up to eight SRV record values.

回應八個 record,但應該是可以註冊超過八個吧... (i.e. 每次都回不一樣)

自建服務 (像是 Cassandra 或是 ScyllaDB) 可以直接用這個服務掛上去,就不用自己架 Consul 了。


Amazon Route 53 Auto Naming is available in US East (N. Virginia), US East (Ohio), US West (Oregon), and EU (Ireland) regions.

Slashdot 名字的由來

在 20 年紀念文 (懷舊文) 中 Rob Malda 提到了 Slashdot 名字的由來:「A Pre-History of Slashdot」。

I originally used the name ‘slashdot’ on my desktop a year earlier when I got my first static IP in the Voorhees Hall dorm room I shared with Dave. Back in 1996, our floor was the first in all of Hope College to be granted 24/7 high speed internet access.

宿舍機器的名字 XDDD

Let's Encrypt 的官方版本 Client 將會改名

Let's Encrypt 的官方 Client 決定改名,不過目前還沒有公佈新的名字:「New Name, New Home for the Let's Encrypt Client」。


[...] we want the client to be distributable and customisable without having to create a complex process for deciding whether customized variants are appropriate for use with Let’s Encrypt trademarks.

另外一個是希望之後有其他的 CA 也可以用:

Another reason is that we want it to be clear that the client can work with any ACME-enabled CA in the future, not just Let’s Encrypt.

奇怪的 RFC:Naming Things with Hashes

看到「RFC 6920: Naming Things with Hashes」這個,看日期是 April 2013,就在想是不是四月一號發的... 但內容看起來還頗有用的,有種 distributed web 的味道?文件裡給的範例長這樣:

   <title>ni: relative URI test</title>
   <base href="ni://example.com">
   <p>Please check <a href="sha-256;f4OxZX...">this document</a>.
     and <a href="sha-256;UyaQV...">this other document</a>.
     and <a href="sha-256-128;...">this third document</a>.

目前是 Propsed Standard,所以是怎樣呢...