Posts on Logan's Nest

Taxman, an Australian Pay Calculator

Mon, 10 Aug 2026 00:00:00 +0000

There are plenty of Australian pay calculators around, but they all bury the answer under ads, pop-ups, or a broker form that wants your email first. I got sick of it and built my own, same as my tax invoice generator.

Why Sentry events silently vanished from our Fargate Node app

Wed, 20 May 2026 00:00:00 +0000

TL;DR

Sentry’s Node SDK uses Node’s native https.Agent, which in Node 18+ does Happy Eyeballs dual-stack connections by default. When DNS returns AAAA records but the host (e.g. an ECS Fargate ENI) has no IPv6 routing, the IPv6 connect attempts don’t fail fast — they hang until the agent’s default 2-second timeout, producing AggregateError [ETIMEDOUT] and silently dropping the event. curl from the same host works fine because curl falls back to IPv4 in milliseconds. The fix is one line: tell the Sentry transport to force IPv4 via a custom httpModule.

Bypassing AWS Lambda's 4 KB env var limit

Thu, 07 May 2026 00:00:00 +0000

TL;DR

Lambda caps the total Environment.Variables map at 4 KB. There’s no AWS feature that auto-hydrates env vars from SSM at runtime. The cleanest way around it is a tiny Go binary wired up as AWS_LAMBDA_EXEC_WRAPPER that fetches SSM params at cold start and syscall.Execs the runtime, so the handler sees process.env.X exactly as if it had been set inline. Zero application changes; one Lambda layer.

CloudFront Anycast IP

Thu, 09 Oct 2025 00:00:00 +0000

I recently worked with a new AWS product called CloudFront Anycast IP, which costs $3,000/month. After testing it, I found the offering to be quite misleading, so I’m sharing my findings here.

Australian SMS OTP Burner

Fri, 04 Jul 2025 00:00:00 +0000

This idea first came to me when Telstra introduced their SMS API a few years back. I kicked off a mini project around it, but couldn’t fully bring it to life due to time constraints.

WireGuard Setup

Fri, 14 Mar 2025 00:00:00 +0000

I spent some time figuring out how WireGuard works and found the guidelines, including the official ones, to be rather complex. So, I’m jotting down my learnings here.

If you can’t be bothered with all the key and config files, https://www.wireguardconfig.com/ provides one click setup for that with QR code.

Australian Tax Invoice Generator

Mon, 24 Feb 2025 00:00:00 +0000

As I embarked on my first contractor gig, I was asked to provide my own tax invoice. Having dealt with countless invoices over the years, I assumed it would be a simple task. To my surprise, most tax invoice generators out there require payment—some even take a percentage of the transaction, like Stripe. Others, for something as basic as a Word or Excel template, ask for your email just to send you spam.

CloudFront Functions with Dynamic Origin Pointing to Another CloudFront

Wed, 05 Feb 2025 00:00:00 +0000

At re:Invent 2024, CloudFront Functions introduced new features, including the ability to dynamically change the origin host.

Previously, this wasn’t possible as the Host header was read-only for CloudFront viewer requests.

Home Assistant with DSM7

Thu, 04 Jan 2024 00:00:00 +0000

https://gist.github.com/maeneak/851e883eca7cddd7114f7eaed201ca9d has a pretty good guide in there.

Create a data directory & docker-compose file:

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version: '3'

services:
 hassio:
 image: homeassistant/amd64-hassio-supervisor
 container_name: hassio_supervisor
 privileged: true
 security_opt:
 - seccomp:unconfined
 - apparmor:unconfined
 environment:
 - HOMEASSISTANT_REPOSITORY=homeassistant/qemux86-64-homeassistant
 - SUPERVISOR_SHARE=/volume1/docker/homeassistant
 - SUPERVISOR_NAME=hassio_supervisor
 volumes:
 - /volume1/docker/homeassistant:/data
 - /var/run/docker.sock:/var/run/docker.sock
 - /var/run/dbus:/var/run/dbus

Then run docker-compose up -d and you should be good to go.

Run a debug prob in a kubernetes cluster with gatekeeper

Fri, 27 Oct 2023 00:00:00 +0000

When attempting to run kubectl debug <node> -it --image=<image> blocked due to gatekeeper, you can do about the same with normal kubectl run command like below:

kubectl run logan-tmp-shell --rm -i --tty --image <image>

Capture bash command error in file

Wed, 12 Oct 2022 00:00:00 +0000

Neat trick to capture STDERR into a text file for the next command but also exit with the preserved exit code after then.

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gradle \
 build \
 2> >(tee error.log >&2)

EXIT_CODE=${PIPESTATUS[0]}

if [[ -s "error.log" ]] && [[ ${EXIT_CODE} -ne 0 ]]
then
 cat error.log | buildkite-agent annotate --style "error"
fi

exit $EXIT_CODE

Lookup CMK for a test in CDK

Tue, 06 Sep 2022 00:00:00 +0000

Add a CMK in CDK was easy, then when I looked into a way to reference the resource using findResources, faced constant failure as for some reason CDK can’t really pickup the key based on the alias.

Extract TLD from string by bash

Fri, 25 Jun 2021 00:00:00 +0000

Faced this interesting use case when I need to extract TLD from the provided hostname string.

Realised simply slicing two bits from the last won’t cut when the hostname comes with mixed .com and .co.uk

Old Twitter Deleter

Thu, 24 Jun 2021 00:00:00 +0000

https://twitter.han.life/

My new personal project automatically clean up old tweets.

I wrote some technical detail why this is a thing in the git README

Largely motivated by all tools available doing this either asks for payment like this and this or need some tech knowledge to setup & run the script.

Add HTTP auth username into envoy proxy logging

Tue, 01 Jun 2021 00:00:00 +0000

Oddly couldn’t find any useful copy & paste solution for this.

As always, base64 decoding and split function copy & pasted from somewhere else.

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http_filters:
- name: envoy.filters.http.lua
 typed_config:
 "@type": type.googleapis.com/envoy.extensions.filters.http.lua.v3.Lua
 inline_code: |
 b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
 function base64decode(data)
 data = string.gsub(data, '[^'..b..'=]', '')
 return (data:gsub('.', function(x)
 if (x == '=') then return '' end
 local r,f='',(b:find(x)-1)
 for i=6,1,-1 do r=r..(f%2^i-f%2^(i-1)>0 and '1' or '0') end
 return r;
 end):gsub('%d%d%d?%d?%d?%d?%d?%d?', function(x)
 if (#x ~= 8) then return '' end
 local c=0
 for i=1,8 do c=c+(x:sub(i,i)=='1' and 2^(8-i) or 0) end
 return string.char(c)
 end))
 end
 function split(s, delimiter)
 result = {};
 for match in (s..delimiter):gmatch("(.-)"..delimiter) do
 table.insert(result, match);
 end
 return result;
 end
 function envoy_on_request(request_handle)
 local auth_header = request_handle:headers():get("Authorization")
 if auth_header ~= nil then
 local auth_token = split(auth_header," ")
 if auth_token[1] == "Basic" then
 local auth_decoded = split(base64decode(auth_token[2]),":")
 request_handle:headers():replace("x-username", auth_decoded[1])
 auth_header = null
 auth_token = null
 autn_decoded = null
 end
 end
 end
- name: envoy.filters.http.router
 typed_config: {}

Then it can be added into the log by using %REQ(x-username)% from envoy.extensions.access_loggers.file.v3.FileAccessLog.format

Sony WH-1000XM4 noise issue

Thu, 08 Apr 2021 00:00:00 +0000

My less than 6m old Sony WH-1000XM4 suddenly started making wind like static noise from the right side only.

After a few tests, I’ve confirmed it’s a persistent issue hence sent it back for RMA process.

fargate container healthcheck

Mon, 18 Jan 2021 00:00:00 +0000

Long story in short, unlike what https://docs.aws.amazon.com/AmazonECS/latest/APIReference/API_HealthCheck.html suggests, fargate doesn’t have curl.

For some reason it does have wget, so "command": [ "CMD-SHELL", "wget -q -O - ${healthcheck_endpoint} || exit 1" ] works as expected.

Exclude a Kotlin subproject from Gradle Jacoco

Mon, 21 Dec 2020 00:00:00 +0000

In my project, one of the subproject is NodeJS hence the usual Jacoco setup:

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tasks.withType(Test) {
 finalizedBy jacocoTestReport
}

doesn’t work as Jacoco fails since it can’t locate test execution binary for the nodeJS project.

TrueImage DS918+

Mon, 29 Jun 2020 00:00:00 +0000

TrueImage can’t be installed on DS918+

To bypass it, download the docker package from below URL and get a hex editor.

https://archive.synology.com/download/Package/spk/AcronisTrueImage/1.0.0000/AcronisTrueImage-dockerx64-1.0.0000.spk

Open the file and edit archtype dockerx64 to x86_64 then ensure backfill the reduced characters into places like description as it does have size check.

[BASH] Repeat Build Step

Mon, 22 Jun 2020 00:00:00 +0000

When you need to print out YAML build step for multiple environments.

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DEPLOY_ENVS=(staging:account1 staging2:account2)

build_pipeline_step() {
 yaml_orig=$1
 for DEPLOY_ENV in "${DEPLOY_ENVS[@]}"
 do
 IFS=':' read -r -a DEPLOY_ENV_ARRAY <<< "$DEPLOY\_ENV"
 DEPLOY_ENV=${DEPLOY_ENV_ARRAY[0]}
 DEPLOY_ACCOUNT=${DEPLOY_ENV_ARRAY[1]}
 yaml="$(sed "s/DEPLOY_ENV/${DEPLOY_ENV}/g" <<< "$yaml_orig")"
 yaml="$(sed "s/DEPLOY_ACCOUNT/${DEPLOY_ACCOUNT}/g" <<< "$yaml")"
 echo "$yaml"
 done
 echo " - wait"
}

build_pipeline_step "$(cat <<EOF
 - label: 'DEPLOY_ENV - DEPLOY_ACCOUNT'
 commands: "echo hello DEPLOY_ENV"
EOF
)"

CloudFlare Log Search

Fri, 19 Jun 2020 00:00:00 +0000

Get the Zone ID
Select domain name from the dashboard then zone ID will show on bottom right corner.
Get the API Key
Select log search template to give minimum privilege
(Optional) Look up the fields available

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curl -s -H "X-Auth-Email: <EMAIL>" -H "Authorization: Bearer <API KEY>" "https://api.cloudflare.com/client/v4/zones/<Zone ID>/logs/received/fields" | jq .

4. Run Log Search (modify date & time bit as you need)

AWS TGW VPN using Unify UDM

Sat, 13 Jun 2020 00:00:00 +0000

Transit Gateway (TGW) is a managed cloud router service provided by AWS and it supports direct VPN attachment.

The setup is little bit tricky as UDM doesn’t support BGP.

1. Create a Customer Gateway
Select Dynamic routing and enter your router public IP

Amazon SES with Postfix in Ubuntu

Fri, 15 May 2020 00:00:00 +0000

Was looking at https://docs.aws.amazon.com/ses/latest/DeveloperGuide/postfix.html but it’s not really working as it’s missing some key commands.

Install packages apt install -y postfix libsasl2-modules\ select ’no configuration'

Config files

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cp /usr/share/postfix/main.cf.debian /etc/postfix/main.cf

in /etc/postfix/main.cf

Selenoid Parallel CI testing

Tue, 12 May 2020 00:00:00 +0000

Selenoid is handy tool to manage test runner with minimum efforts.
As it uses own dependent containers by itself, need to maintain single Selenoid run per build agent.

docker-compose.yml

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services: 
 e2e-test-runner:
 networks:
 selenoid: null
 depends_on:
 - selenoid
 build:
 context: .
 dockerfile: end-to-end/Dockerfile
 environment:
 - BUILDKITE
 - NEXUS_USERNAME
 - NEXUS_PASSWORD
 - PAYLATER_VERSION
 - CHROME_PROFILE_DIR=/tmp/chrome_profile
 - SEL_JUP_SELENIUM_SERVER_URL=http://selenoid:4444/wd/hub/
 - GRADLE_USER_HOME=/app/.gradle
 volumes:
 - $PWD/end-to-end/build/reports:/app/end-to-end/build/reports
 - $PWD/build/reports:/app/build/reports
 - /var/run/docker.sock:/var/run/docker.sock


 selenoid:
 image: aerokube/selenoid:latest-release
 networks:
 selenoid: null
 volumes:
 - "/tmp/selenoid/video:/opt/selenoid/video:delegated"
 - "/tmp/selenoid/logs:/opt/selenoid/logs:delegated"
 - "$PWD/end-to-end/selenoid:/etc/selenoid:delegated"
 - "/var/run/docker.sock:/var/run/docker.sock"
 expose:
 - "4444"
 environment:
 - OVERRIDE_VIDEO_OUTPUT_DIR=/tmp/selenoid/video
 command: ["-conf", "/etc/selenoid/browsers.json", "-video-output-dir", "/opt/selenoid/video", "-log-output-dir", "/opt/selenoid/logs","-save-all-logs","-disable-privileged", "-container-network", "selenoid"]

CI Pipeline (BK)

Salesforce CLI with Docker in AWS

Fri, 28 Jun 2019 00:00:00 +0000

Auth was the tricky part as the normal auth requires a browser session rather than taking it from the CLI prompt.

Step 1. Create Dockerfile

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FROM node:9.9.0-alpine 
RUN npm install sfdx-cli --global 
RUN sfdx --version 
RUN sfdx plugins --core

Step 2. Generate auth URL from your laptop and push into SSM

Pooq Proxy

Sun, 14 Jan 2018 00:00:00 +0000

This is my current setup for watching Pooq in Australia for anyone interested. With local proxy, below 4k streaming (UHD) seems alright with NBN via AussieBB. TPG might have better throughput as they have PPC-1 submarine cable.

Generate custom x509 certificate in Okta

Sun, 19 Nov 2017 00:00:00 +0000

* Requires API key with admin access, least for the target app

Obtain app name & label using app ID

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curl -v -X GET \
-H "Accept: application/json" \
-H "Content-Type: application/json" \
-H "Authorization: SSWS ${api_token}" \
"https://[okta_instance].okta.com/api/v1/apps/[app_id]"

Generate custom certificate and capture ‘kid’ value from response

Selenium test with docker-compose

Tue, 23 May 2017 00:00:00 +0000

Sample config file when using selenium standalone during test.

docker-compose YAML

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version: '3'
services:
 test:
 depends_on:
 - selenium
 environment:
 - E2ETEST_HOST=test
 - SELENIUM_PORT=4444
 - SELENIUM_HOST=selenium
 build:
 context: .
 dockerfile: Dockerfile
 ports:
 - "80:80"
 - "443:443"
 command: run_test.sh
 selenium:
 image: selenium/standalone-chrome
 ports:
 - "4444:4444"

nightwatch config sample

AWS KMS - two liners

Thu, 18 May 2017 00:00:00 +0000

For binary encrypted output:

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aws kms encrypt --region ap-southeast-2 --key-id alias/blah --plaintext fileb://blah --output text --query CiphertextBlob | base64 --decode > blah.enc
aws kms decrypt --ciphertext-blob fileb://blah.enc --output text --query Plaintext | base64 --decode

For base64 encrypted output:

User Profile Service failed the logon. User profile cannot be loaded.

Sun, 15 Jan 2017 00:00:00 +0000

https://support.microsoft.com/en-us/contact/menu/software/windows/ts/

https://support.microsoft.com/en-au/help/947215/you-receive-a-the-user-profile-service-failed-the-logon-error-message

Had to contact Microsoft support to receive default file. Download

Curl net performance test

Thu, 15 Dec 2016 00:00:00 +0000

Print out CloudFront X-Amz-Cf-Id when response time is slower than set threshold.

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#!/bin/bash
 
output=($(curl -I -s -w "Time: %{time_total}\n" http://cf_url.here grep -e X-Amz-Cf-Id -e Time | awk {'print $2'}))
 
id=${output[0]}
time=${output[1]}
compare=0.01
 
if (( $(echo "$time > $compare" |bc -l) )); then
 echo $time - $id >> test_results.txt
fi

Small variation (unrelated to CF)

Replace Mercedes-Benz B250 cabin(pollen) filter replacement DIY

Mon, 21 Nov 2016 00:00:00 +0000

Quoted $300+ from dealer shop which I know a serious rip-off price for mere carbon filter.

Searched eBay, local stock comes with some $100 price tag, still too steep.

Found a German seller, selling compatible filter for approx. $27 for the item and $15 shipping - even made in Germany!

MongoDB to DynamoDB

Wed, 08 Jun 2016 00:00:00 +0000

Attempted to convert rather large mongo dump to dynamo.

Seems like AWS data pipeline is most elegant way to do this if one can workaround with dynamo non-standard json format issue.

Europe Travel 2016

Thu, 28 Apr 2016 00:00:00 +0000

Turkey - Istanbul Good: Nice people and food Bad: Syrian refugees(=security risks), bit too excessive street sales

Turkey is way more developed country than I thought therefore booking cheap hotel was a bit of mistake. It was too cheap as burger king meal is AUD 10 ish hence rather crappy, even housekeeping didn’t given at all time. Also its right next to a Mosque hence 6am morning pray coming from huge speaker was the morning call. Public transport here is quite good so suggest invest bit more money and get somewhere outer city location.

Lets Encrypt nginx SSL certificate renewal via cron

Wed, 18 Nov 2015 00:00:00 +0000

Add below as a cron entry.

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#!/bin/bash
/path/letsencrypt/letsencrypt-auto --server https://acme-v01.api.letsencrypt.org/directory --renew-by-default -a webroot --webroot-path /webroot/ --email youremail --text --agree-tos --agree-dev-preview -d 7979.us -d www.7979.us auth
/etc/init.d/nginx reload

Then configure nginx SSL like below.

F5 AAM Cache for app generated pages

Mon, 16 Nov 2015 00:00:00 +0000

Dynamic content requires cache-control(max-age) and/or expires header to be cached.

The headers also need to be honoured from AAM policy which is not enabled by default.

Debug header decode: wainfodecode [X-WA-INFO header content]

Run HTTP POST request from chrome developer tools

Wed, 11 Nov 2015 00:00:00 +0000

Do this from developer mode console.

May need to load a page from the same domain to avoid cross domain validation failure.

var xhr = new XMLHttpRequest(); xhr.open('POST', 'http://url_here', true); xhr.setRequestHeader('Content-type', 'application/json'); xhr.onload = function () { // do something to response console.log(this.responseText); }; xhr.send('query_here');

Had a car accident in Victoria? Well, too bad.

Wed, 02 Sep 2015 00:00:00 +0000

I assume everyone reading this well aware about how the car insurance works and maybe made a few claims in past for minor scratches and parking mistakes. That covers the vehicle damages then any injuries and losses caused to human will be taken care by TAC. Until I recently had my first major car crush in my life, that was all I know about TAC and no question asked for past decade for paying extra dollars for it.

Contract position

Wed, 13 May 2015 00:00:00 +0000

pros: Market standard is 30% extra compare to similar perm position, pro-rata basis. Can claim expense for pretty much all the things, if there’s any.

cons: 9.5% superannuation 3% agency fee (bit cheaper if you manage your tax bits and indemnity insurance by yourself) 8.3% annual leave (20 working days = 4 weeks) 4.16% personal leave (10 working days = 2 weeks) in total: 24.96%

Unlock Optus ZTE F286

Sat, 09 May 2015 00:00:00 +0000

Looks like this phone is getting remarkably popular with Optus Netflix deal.

The best price for paid unlock code I looked up was $2 which seems… not so reasonable for $15 phone.

rpmlib(FileDigests) / rpmlib(PayloadIsXz) is needed

Wed, 06 May 2015 00:00:00 +0000

This means you are attemping to install a RPM created in CentOS6+ from CentOS5.

For backward compatibility, rebuild rpm like: rpmrebuild -e -p xyz.rpm

Then add below: %define _binary_filedigest_algorithm 1 %define _binary_payload w9.gzdio

gnu parallel

Wed, 29 Apr 2015 00:00:00 +0000

So I was testing this today and this is the message I saw when I ran it:

`Academic tradition requires you to cite works you base your article on. When using programs that use GNU Parallel to process data for publication please cite:

Ports for WDS

Tue, 31 Mar 2015 00:00:00 +0000

Ports for WDS

Google search said ‘The following TCP ports need to be open for WDS to work across a firewall: 135 and 5040 for RPC and 137 thru 139 for SMB.’

Query of the century

Thu, 05 Feb 2015 00:00:00 +0000

My co-worker showed me this today and it’s just gorgeous.

BEGIN; CREATE TABLE xyz_tmp (LIKE xyz INCLUDING ALL); COPY xyz_tmp FROM STDIN; ALTER TABLE xyz RENAME TO xyz_old; ALTER TABLE xyz_tmp RENAME TO xyz; DROP TABLE xyz_old; COMMIT;

Hue with LDAP doesn't start up after Cloudera Manager upgrade

Tue, 03 Feb 2015 00:00:00 +0000

Latest Cloudera Manager omit ldap_username_pattern entry from hue.ini build process.

Paste below into safety valve as a workaround.

[desktop] [[ldap]] ldap_username_pattern="username=,ou=user,dc=7979,dc=us"

P.S: Had some weird experience without ""

How to get free credit reports in Australia

Thu, 11 Dec 2014 00:00:00 +0000

Generally takes 10 business days.

1. Experian Drop an email to creditreport@au.experian.com Attach scanned copy of your driver’s license and medicare

2. Veda https://forms.mycreditfile.com.au/Apply/Personal/Credit/Step1.aspx?form=FreeCreditFile

3. D&B https://www.checkyourcredit.com.au/MyAccount/Order/StandardService

Merging multiple avro files into single file using python

Tue, 02 Dec 2014 00:00:00 +0000

Couldn’t find any good example from Web so made one by myself.

It has bits that handling header and footer(it’s using bogus footer as it was really FYI only thing for me but you may need to recreate it if it does matter) as well.

Catches novated lease company never tell you

Fri, 07 Nov 2014 00:00:00 +0000

Some knowledges I have accuqired from using novated lease for last 2+ years.

Assuming you know the basics from google or sales pitches from lease management company, here are the things they never tell you.

CDH 5.2.0 spark history server issue

Fri, 17 Oct 2014 00:00:00 +0000

5.2.0-1.cdh5.2.0.p0.36 has been released couple of days ago.

It has a small bug with its spark bit, which make unable to start spark history server.

The problem is the default value of Spark History Location (=spark.eventLog.dir) is /user/spark/applicationHistory and it doesn’t append hdfs header by default, hence get recognised as local drive rather than HDFS.

Simple pull to refresh

Tue, 30 Sep 2014 00:00:00 +0000

1. Get stuffs from https://github.com/zippy1978/jquery.scrollz

2. Add below in head section.

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<script src="//code.jquery.com/jquery-1.9.1.min.js"></script>
<link rel="stylesheet" href="jquery.scrollz.css"/>
<script src="jquery.scrollz.min.js"></script>

3. Add an object with matching id. e.g)

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<table id="main">

4. Add below in body section.

Foreman + Puppet autosign.conf doesn't work

Mon, 08 Sep 2014 00:00:00 +0000

Issue: 1. Foreman generates auto sign entry when /provision called first time. (boot loader hit) 2. Once OS is done and call puppet agent run, CSR doesn’t get auto-signed. - stays in ‘pending’ status forever

Log compression for Cloudera Manager Hadoop

Fri, 04 Jul 2014 00:00:00 +0000

Cloudera manager uses standard log4j which doesn’t support compression by itself.

It requires Apache Extras™ for Apache log4j™ (http://logging.apache.org/log4j/extras/) or maybe log4j2.

Load log4j-(latest version).jar by placing it under /lib of CDH parcel or custom import.

Puppet Dell iDRAC control

Fri, 04 Jul 2014 00:00:00 +0000

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if $::manufacturer == 'Dell Inc.' {
 exec { 'Disable DRAC SNMP':
 command =>; 'racadm config -g cfgOobSnmp -o cfgOobSnmpAgentEnable 0',
 path =>; '/opt/dell/srvadmin/sbin:/bin',
 onlyif =>; '/usr/bin/test `/opt/dell/srvadmin/sbin/racadm getconfig -g cfgOobSnmp -o cfgOobSnmpAgentEnable` -eq 1',
 }
}

Yea, I think onlyif bit is not nice.

Generate Bacula client cert/key pair via Puppet

Wed, 28 May 2014 00:00:00 +0000

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exec {'generate client key file':
command => '/usr/bin/openssl genrsa -out /bacula/bacula-client.key 2048;chmod 600 /bacula/bacula-client.key',
creates => '/bacula/bacula-client.key',
require => Package['bacula-fd'],
}

exec {'generate client cert file':
command => '/usr/bin/openssl req -new -key /bacula/bacula-client.key -x509 -subj "/C=AU/ST=somewhere/L=somewhere/O=something/CN=something" -out /bacula/bacula-client.cert',
creates => '/bacula/bacula-client.cert',
require => [ Package['bacula-fd'], Exec['generate client key file'], ],
}

exec {'combine client key and cert files':
notify => Service["bacula-fd"],
command => '/bin/cat /bacula/bacula-client.key /bacula/bacula-client.cert > /bacula/bacula-client.pem;chmod 600 /bacula/bacula-client.pem',
creates => '/bacula/bacula-client.pem',
require => [ Package['bacula-fd'], Exec['generate client key file'], Exec['generate client cert file'], ],
}

Would be nicer if I can send them to backup location but doesn’t really matter as there’s master key.

Convert .xva to .qcow2 (or raw)

Thu, 23 Jan 2014 00:00:00 +0000

Figured out while running below work.

Got the hint from: http://jolokianetworks.com/70Knowledge/Virtualization/Converting_from_Citrix_XenServer_to_Xen_open_source/Xenmigrate.py And got modded .py from: http://pastebin.com/MK5Da8CB

1. run tar -xvf {image}.xva

2. python xenmigrate.py –convert=./Ref\:directory_here/ test.img

Run Citrix NetScaler VPX from KVM

Thu, 23 Jan 2014 00:00:00 +0000

1. Download Hyper-V image and extract .vhd

2. Covert it via running: qemu-img convert -O qcow2 NSVPX-ESX-10.1-119.7_nc-disk1.vhd NSVPX-XEN-10.1-119.7_nc.qcow2

3. Create a VM, mount the image.

4. Login via nsroot/nsroot and run ‘config ns’ for initial network setup. Oddly, this menu doesn’t list routing option including default gateway. Add it manually via ‘config add route 0.0.0.0 255.255.255.255 your_gateway_ip’

Bacula daily (or weekly) email report for postgres DB

Tue, 21 Jan 2014 00:00:00 +0000

This now moved to: https://github.com/logan-han/sysadmin_stuffs/blob/master/bacula_report.sh

Dell Chat Support

Mon, 06 Jan 2014 00:00:00 +0000

Sick of telling phonetic code over the phone?

Try dell chat support here: http://www.dell.com/support/incidents/us/en/555/chat/tagchange

Copy & paste friendly and upload attachment feature available.

It only works till midnight CST.

Disable msi with minimal interruption

Mon, 14 Oct 2013 00:00:00 +0000

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ifconfig eth0 down
rmmod bnx2
modprobe bnx2 disable_msi=1
ifconfig eth0 up
route add -net default netmask 0.0.0.0 gw [default gw here] eth0

For bonding interface:

3TB partition support in Linux

Tue, 31 Jul 2012 00:00:00 +0000

Make a GPT partition:

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parted /dev/sda
mklabel gpt
unit TB
mkpart primary 0 -0
quit

Format with 1% root reservation:

mkfs.ext4 -m1 /dev/sda1

Note: HP Array controller may require firmware update for 3TB disk support.

How to increase VM disk size without re-deploy the machine

Fri, 13 Jul 2012 00:00:00 +0000

Ref: http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&docTypeID=DT_KB_1_1&externalId=1006371

[root@demo ~]# fdisk /dev/sda

-Create a primary partition-

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[root@demo ~]# fdisk -l

Device Boot Start End Blocks Id System
/dev/sda1 * 1 64 512000 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 64 1306 9972736 8e Linux LVM
/dev/sda3 1306 6527 41942367+ 83 Linux

[root@demo ~]# pvcreate /dev/sda3
[root@demo ~]# vgextend vg_demo /dev/sda3

[root@demo ~]# vgdisplay vg_demo | grep Free
Free PE / Size 10239 / 40.00 GiB

[root@demo ~]# lvextend -L+40.00G /dev/vg_demo/lv_root

[root@demo ~]# resize2fs /dev/vg_demo/lv_root

Note: I wouldn’t do this for any production system as it looks pretty inefficient way to extend volume size.

L2L VPN with ASA - Connection established but no packet coming from one side

Thu, 05 Jul 2012 00:00:00 +0000

Symtom:

1. Connection established.

2. 0 en/decapsulated packet from one side.

Solution:

Seems like ASA pickup Dynamic VPN profile if it has higher priority than L2L.

Resolved after change dynamic profile priority.

Fix Hadoop leap second bug without rebooting

Tue, 03 Jul 2012 00:00:00 +0000

Source: http://blog.wpkg.org/2012/07/01/java-leap-second-bug-30-june-1-july-2012-fix/

Applied our hadoop node having CPU usage issue. (CentOS)

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service ntpd stop
date `date +”%m%d%H%M%C%y.%S”`
service ntpd start

Works like a charm!

Change iMessage & Facetime phone number in case of verification failure

Sun, 24 Jun 2012 00:00:00 +0000

Happened me after carrier change. Keep picking up SIM build-in number rather than my old number ported in later.

1. Turn off both facetime & imessage.
2. reset network settings from general settings.
3. make sure settings->phone->my number has your number.
4. Turn on facebook & imessage.

Device credential for Cisco license lookup and transfer

Wed, 16 May 2012 00:00:00 +0000

https://tools.cisco.com/SWIFT/LicensingUI/LicenseAdminServlet/licenseLookup

in CLI:

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license save credential flash0:/credentials.lic 
more flash0:/credentials.lic 

Try SSH if you can’t get full strings from serial connection.

ZeroMQ - PHP client & Python server with multi part message example

Wed, 02 May 2012 00:00:00 +0000

Using pyobj or php data serialisation is not an option in this case..

Client:

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<?php 
$context = new ZMQContext(); 
$requester = new ZMQSocket($context, ZMQ::SOCKET\_REQ); 
$requester->connect("tcp://localhost:9999"); 
$requester->send("Filename",ZMQ::MODE\_SNDMORE); 
$requester->send("Log",ZMQ::MODE\_NOBLOCK); 
?> 

Server:

hubot pandora bot adapter

Mon, 30 Apr 2012 00:00:00 +0000

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# Chat with pandora bot
#
# ai <anything> – PANDORA AI
#

QS = require “querystring”
xml2js = require ‘xml2js’

module.exports = (robot) ->
 robot.respond /(ai|AI)( me)? (.*)/i, (msg) ->
 user = msg.message.user.name
 query = msg.match[3]
 botid = “meh”
 parser = new xml2js.Parser({explicitArray: true})
 msg.http(“http://www.pandorabots.com/pandora/talk-xml”)
 .query({
 botid: botid
 custid: user
 input: query
 })
 .post() (err, resp, body) ->
 parser.parseString body, (err, result) ->
 #console.log(result.that)
 msg.send result.that

cloudmailin hipchat hubot script

Fri, 20 Apr 2012 00:00:00 +0000

Took really long time to deduce workaround… :S
Set cloudmailin as
http://blah.herokuapp.com/hubot/cloudmailin/room_id

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# Cloudmailin

http = require(‘http’)
querystring = require(‘querystring’)
auth_token = “supa-secret”

module.exports = (robot) ->
 robot.router.post ‘/hubot/cloudmailin/:room’, (req, res) ->
 post_data = querystring.stringify({
 room_id: req.params.room,
 message: “#{req.body.from} – #{req.body.subject}<br>#{req.body.html}”,
 from: “MailMan”
 })
 post_options = {
 host: ‘api.hipchat.com’,
 port: 80,
 path: ‘/v1/rooms/message?auth_token=’+auth_token,
 method: ‘POST’,
 headers: {
 ‘Content-Type’: ‘application/x-www-form-urlencoded’,
 ‘Content-Length’: post_data.length
 }
 }

 post_req = http.request post_options, (res) ->
 res.on ‘data’, (chunk) ->
 console.log(‘Response: ‘ + chunk)
 post_req.write post_data
 post_req.end()
 res.writeHead 200, { ‘Content-Length’: 0 }
 res.end()

Python - write compressed log file into HDFS for hadoop hive mapreduce

Thu, 01 Mar 2012 00:00:00 +0000

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import pyhdfs
from cStringIO import StringIO
import binascii

-snip-

#Set hdfs connection info
hdfsaddress = “namenode”
hdfsport = 12345
hdfsfn = “filename”

#gzip compression level
clevel = 1

-snip-

 logger.info(“Writing compressed data into ” + hdfsfn + “.gz”)
 #open hdfs file
 fout = pyhdfs.open(hdfs, hdfsfn + “.gz”, “w”)
 #compress the data and store it in compressed_data
 buf = StringIO()
 f = gzip.GzipFile(mode=’wb’, compresslevel=clevel,fileobj=buf)
 try:
 f.write(concatlog)
 finally:
 f.close()
 compressed_data = buf.getvalue()
 #write compressed data into hdfs
 pyhdfs.write(hdfs,fout,compressed_data)
 #close hdfs file
 logger.info(“Writing task finished”)
 pyhdfs.close(hdfs,fout)
-snip-

Facebook scribe with hdfs

Fri, 17 Feb 2012 00:00:00 +0000

packages:
libevent
hadoop-0.20-libhdfs
JDK for hdfs support

Boost
http://sourceforge.net/projects/boost/
./bootstrap.sh
./bjam
./bjam install

thrift
download form http://thrift.apache.org/download/
./configure
make
make install

fb303
it’s in /contrib/fb303

./bootstrap.sh
./configure CPPFLAGS="-DHAVE_INTTYPES_H -DHAVE_NETINET_IN_H"
(To avoid compile error, recompile thrift with this option if it doesn’t work)
make
make install

Flume DFO local storage usage check

Mon, 30 Jan 2012 00:00:00 +0000

It might be useful when flume driver failed.

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!/usr/bin/perl
#Check flume DFO directory size

sub trim($);
use strict;
use warnings;

my $exit=0;
my $backlog_size = `du -s flume | awk {‘print \$1’}`;
$backlog_size = trim($backlog_size);

if ( !$ARGV[0] || !$ARGV[1])
{
########################### Usage of the plugin
print “check_flume_backlog critical_size warning_size \n”;
exit 0;
}

######################### Case 1 if State is Critical
if ($backlog_size > $ARGV[0])
{
print “Critical: “.$backlog_size.”b\n”;
exit 2;
}

######################## Case 2 if State is Warning
if($backlog_size > $ARGV[1] || $backlog_size == 0)
{
print “Warning: “.$backlog_size.”b\n”;
exit 1;
}

######################## Case 3 if State is OK
if($backlog_size < $ARGV[0] && $backlog_size < $ARGV[1])
{
print “OK: “.$backlog_size.”b\n”;
exit 0;
}

sub trim($)
{
 my $string = shift;
 $string =~ s/^\s+//;
 $string =~ s/\s+$//;
 return $string;
}

And for centralised monitoring..

Default fixed version value when creating an issue in JIRA

Tue, 24 Jan 2012 00:00:00 +0000

You can try to add some JavaScript code to the field that will perform required operation for you, in this case it should be ‘Fix Version’ field. You can refer to this documentation as a guideline:
http://confluence.atlassian.com/display/JIRACOM/Using+JavaScript+to+Set+Custom+Field+Values

delete mplayerx history

Fri, 30 Dec 2011 00:00:00 +0000

http://code.google.com/p/mplayerx/issues/detail?id=517

launch Terminal, and use the command to clear the history - tested.

defaults delete org.niltsh.MPlayerX.LSSharedFileList RecentDocuments

prevent history being created, not tested defaults write org.niltsh.MPlayerX NSRecentDocumentsLimit 0

Atlassian crowd authentication directory address force update

Wed, 28 Dec 2011 00:00:00 +0000

When you migrate atlassian product (confluence, jira etc etc) to somewhere else, your backup file includes fixed crowd address which is not gonna work for some cases.

Since Atlassian moved directory configuration from fixed config file to database,
you will need to execute following:

Cisco Router config for ACME PACKET

Wed, 21 Dec 2011 00:00:00 +0000

sip-ua

authentication username -snip- password 7 -snip-

registrar dns:realm.domain expires 3600

sip-server dns:realm.domain

connection-reuse

voice service voip

no ip address trusted authenticate

allow-connections sip to sip

no supplementary-service sip moved-temporarily

Using additional public ip address over pppoe nat with cisco router

Fri, 30 Sep 2011 00:00:00 +0000

To allocate router a non-NAT IP (for AWS VPC etc etc)

1. Create a loopback interface and put given ip & subnet 2. profit!

Otherwise,

ip nat inside source route-map NONAT interface Dialer1 overload ip nat inside source static 192.168.?.? PUBLIC_IP_HERE