Home » 2017 » November

Amazon S3 的流量,以及 S3 與 Glacier 都推出 Select 功能

Twitter 上看到會場的照片,Amazon S3 單一 region 就有 37 Tb/sec 的量:

在這種量下面對 DDoS 沒什麼感覺 XDDD

另外是 Amazon S3 與 Amazon Glacier 都推出了 Select 功能:「S3 Select and Glacier Select – Retrieving Subsets of Objects」。

看示範的程式碼就可以看出用途了,原文中間那段有 sytax error,我這邊就幫忙修掉了:

handler = PrintingResponseHandler()
s3 = boto3.client('s3')
response = s3.select_object_content(
    Bucket="super-secret-reinvent-stuff",
    Key="stuff.csv",
    SelectRequest={
        'ExpressionType': 'SQL',
        'Expression': 'SELECT s._1 FROM S3Object AS s',
        'InputSerialization': {
            'CompressionType': 'NONE',
            'CSV': {
                'FileHeaderInfo': 'IGNORE',
                'RecordDelimiter': '\n',
                'FieldDelimiter': ',',
            }
        },
        'OutputSerialization': {
            'CSV': {
                'RecordDelimiter': '\n',
                'FieldDelimiter': ',',
            }
        }
    }
)

這樣可以大幅降低 I/O,節省成本:

Glacier Select 也是類似的想法,不需要整包拉出來再處理,可以在一開始就設定條件。

Amazon Aurora 的 Serverless 與 Multi-master

Amazon Aurora 推出了兩包玩意,第一包是 Serverless,讓需要人介入的情況更少:「In The Works – Amazon Aurora Serverless」。

在 Serverless 的第一個重點是支援以秒計費:

Today we are launching a preview (sign up now) of Amazon Aurora Serverless. Designed for workloads that are highly variable and subject to rapid change, this new configuration allows you to pay for the database resources you use, on a second-by-second basis.

然後是極為快速的 auto-scaling:

The endpoint is a simple proxy that routes your queries to a rapidly scaled fleet of database resources. This allows your connections to remain intact even as scaling operations take place behind the scenes. Scaling is rapid, with new resources coming online within 5 seconds

這兩個組合起來,讓使用端可以除了在 Amazon EC2 上可以快速 scale 外,後端的資料庫也能 scale 了...

第二個是 Multi-master 架構:「Sign Up for the Preview of Amazon Aurora Multi-Master」。

Amazon Aurora Multi-Master allows you to create multiple read/write master instances across multiple Availability Zones. This enables applications to read and write data to multiple database instances in a cluster, just as you can read across Read Replicas today.

(話說我一直都誤以為 Aurora 是 R/W master...)

Anyway,這個功能不知道怎麼疊上去的... 不笑得會不會有嚴重的 distributed lock issue,反而推薦大家平常都寫到同一台 (像是 PXC 就會這樣)。

Amazon DynamoDB 跨區 Replication 以及備份

Amazon DynamoDB 實做了全球性的 replication,以及備份功能:「Amazon DynamoDB Update – Global Tables and On-Demand Backup」。

跨區 replication 的功能讓每個 region 都可以存取當地機房的 DynamoDB:

Global Tables – You can now create tables that are automatically replicated across two or more AWS Regions, with full support for multi-master writes, with a couple of clicks. This gives you the ability to build fast, massively scaled applications for a global user base without having to manage the replication process.

這有點類似 GoogleCloud Spanner 在前陣子也推出全球性服務,但 DynamoDB 提供的比較偏向 NoSQL 而不是 RDBMS。

另外一個限制是跨區同步是 async,會有 replication lag 的問題:

Updates are propagated to other Regions asynchronously via DynamoDB Streams and are typically complete within one second (you can track this using the new ReplicationLatency and PendingReplicationCount metrics).

不過如果是這樣的機制,conflict 的問題不知道怎麼解決... 文章裡面沒看到。

然後目前支援的區域還是有限:

Global Tables are available in the US East (Ohio), US East (N. Virginia), US West (Oregon), EU (Ireland), and EU (Frankfurt) Regions today, with more Regions in the works for 2018.

另外一個是備份與還原機制,有這樣的功能對很多計畫方便不少:

On-Demand Backup – You can now create full backups of your DynamoDB tables with a single click, and with zero impact on performance or availability. Your application remains online and runs at full speed. Backups are suitable for long-term retention and archival, and can help you to comply with regulatory requirements.

而備份還原機制是陸陸續續開放的,區域也有限:

We are rolling this new feature out on an account-by-account basis as quickly as possible, with initial availability in the US East (Northern Virginia), US East (Ohio), US West (Oregon), and EU (Ireland) Regions.

Amazon Lightsail 推出 Block Storage 與 Load Balancer

Amazon Lightsail 推出了 Block Storage (11/14) 與 Load Balancer (11/29):「Introducing additional block storage for Amazon Lightsail」、「Amazon Lightsail adds load balancers with integrated certificate management」。

兩個是不同時間點發表的,當時懶的寫所以這次一起寫...

Block Storage 有不少 VPS 都有提供了,像是 Linode 的「Linode Block Storage (Fremont beta)」(雖然還在 beta)、DigitalOcean 的「Storage on DigitalOcean | Highly available Block Storage」以及 Vultr 的「High Performance and Cheap Block Storage - Vultr.com」。

AWS 算是很早就有這個服務 (Amazon EBS),這邊應該只是把系統整合進來...

另外一個是這幾天推出的 Load Balancer,目前應該只有 Linode 的「Ensure High-Availability with NodeBalancers - Linode」比較知名。AWS 上的 ELB 有不少選擇可以用 (ELB Classic、ALB 以及 NLB),不過公告裡沒特別提到... 比較特別的是提供免費的 SSL Certificate 吧?這在其他家主要得靠 Let's Encrypt 來做,在 AWS 上應該是整合了 ACM

Amazon EC2 推出 T2 Unlimited,可以付費超量使用 CPU

Amazon EC2t2 系列的機器上推出 T2 Unlimited:「T2 Unlimited – Going Beyond the Burst with High Performance」。

這不是新的機種,而是現有的機器上可以超量使用 CPU credit,AWS 會另外收費。

新開的機器與已經開的機器都可以打開:

us-east-1 來算,其實相當便宜,看不出什麼 penalty fee:t2.micro 的 CPU credit 是 10% baseline,每小時單價是 $0.0116,所以先有個 100% 數字是 $0.116 的概念 (如果所有東西都是十倍)。

us-east-1 的 T2 Unlimited 是 $0.05 vCPU-hour,這樣看起來其實不賴?風險應該是在於不保證可以拿到多的 CPU resource...

可能要重新算一下 c4c5 的使用方式了...

另外雖然文章後面寫了一大串,但對照 region 表後,看起來是所有的區域都支援了:(美國政府的 region 除外)

You can launch T2 Unlimited instances today in the US East (Northern Virginia), US East (Ohio), US West (Northern California), US West (Oregon), Canada (Central), South America (São Paulo), Asia Pacific (Singapore), Asia Pacific (Sydney), Asia Pacific (Tokyo), Asia Pacific (Mumbai), Asia Pacific (Seoul), EU (Frankfurt), EU (Ireland), and EU (London) Regions today.

AWS 總算推出跨區 VPC Peering 了...

AWS 總算是開始支援跨區 VPC Peering 了... 這功能喊好久了啊:「Announcing Support for Inter-Region VPC Peering」。

不過目前支援的地區只有這些:

Inter-Region VPC Peering is available in AWS US East (N. Virginia), US East (Ohio), US West (Oregon) and EU (Ireland) with support for other regions coming soon.

算是個開頭... 不然以前都要自己搞 High Availability 的 site-to-site IPsec tunnel。

另外沒看到跨區時有沒有加密... (理論上應該要?)

AWS WAF 提供隨時更新的 Managed Rules

AWS WAF 推出了隨時更新的 Managed Rule:「Ready-to-Use Managed Rules Now Available on AWS WAF」。

這些 ruleset 是由 3rd-party 提供的:

Choose from preconfigured RuleGroups provided in the AWS Marketplace by industry leading security experts: Alert Logic, Fortinet, Imperva, Trend Micro and TrustWave.

然後隨時更新:

Rules are automatically updated as new threats emerge and offer a wide range of protections, including OWASP Top 10 mitigations, bad-bot defenses, and virtual patching against recent CVE’s.

然後是要收費的:

Each RuleGroup is the product of a Seller’s unique expertise, made available to you at an affordable pay-as-you-go price.

AWS Marketplace 的「Managed Rules for AWS WAF - Web Application Firewall」裡拿兩家來看看。

趨勢的「Trend Micro Managed Rules for AWS WAF - WebServer (Apache, Nginx)」與「Trend Micro Managed Rules for AWS WAF - Content Management System (CMS)」都是:

Charge per month in each available region (pro-rated by the hour) $5.00 / unit
Charge per million requests in each available region $0.20 / unit

Imperva 則是提供不一樣的選擇,在「Imperva - Managed Rules for WordPress Protection on AWS WAF」是:

Charge per month in each available region (pro-rated by the hour) $30.00 / unit
Charge per million requests in each available region $0.60 / unit

而「Imperva - Managed Rules for IP Reputation on AWS WAF」則是:

Charge per month in each available region (pro-rated by the hour) $40.00 / unit
Charge per million requests in each available region $0.40 / unit

AWS 環境裡面提供 NTP Service 了 (Amazon Time Sync Service)

以前在 AWS 環境裡都要自己架設兩台可以連外的 NTP server,然後將內部機器指到這兩台上,現在可以用現成的了:「Keeping Time With Amazon Time Sync Service」。

服務放在 169.254.169.123

You can access the service via the link local 169.254.169.123 IP address. This means you don’t need to configure external internet access and the service can be securely accessed from within your private subnets.

然後也有提到 leap second 的解法,用的解法是 leap smearing:

Leap seconds are known to cause application errors and this can be a concern for many savvy developers and systems administrators. The 169.254.169.123 clock smooths out leap seconds some period of time (commonly called leap smearing) which makes it easy for your applications to deal with leap seconds.

先前 AWS 也有 leap time,但不包括 Amazon EC2 這些系統 (EC2 裡的時間是獨立的),不過還是可以看一下 AWS 處理 leap time 的方式,因為這次 NTP Service 就會拿去用了。

最近一次 leap time 是 2016 年底的「Look Before You Leap – December 31, 2016 Leap Second on AWS」,處理的方式跟 2015 年時的方法還是一樣:「Look Before You Leap – The Coming Leap Second and AWS (Updated)」。

類似於下圖左上角這張的變化:

然後全區開放,都可以用了:

This service is provided at no additional charge and is immediately available in all public AWS regions to all instances running in a VPC.

Archives