postconf allow you to list/change postfix configuration.
To list current config, run
postconf -n
To change a configuration, run
postconf -e home_mailbox=Maildir/
Blog
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Amazon Workmail Review
Amazon Workmail is business email hosting like Google G Suite, Office 365, etc..
https://aws.amazon.com/workmail/
Workmail cost $4 per user, comes with 50 GB storage.
It come with all normal access modes like IMAP, POP3, etc..
Webmail is basic with contacts and Calendar.
Configuring WorkMail
You can find instructions to configure email clients at
https://docs.aws.amazon.com/workmail/latest/userguide/clients.html
For IMAP/SMTP, see
https://docs.aws.amazon.com/workmail/latest/userguide/using_IMAP.html
SMTP works with phpmailer, so you can use it with your website to send emails.
What is WorkMail webmail URL?
You can find the Amazon WorkMail webmail URL at
Amazon WorkMail > Organizations
Since i am used to Google G Suite, it feel little hard for me to use.
One thing i noticed is when i sent email, i used to type recipient email address, press tab, enter subject, tag again, type message. This is the workflow i am used to in Google G Suite. When i try same in Amazon Workmail, it did not work because there are too many elements on the compose email screen and i have to press TAB multiple times to get into subject or body field.
All the marked elements here force you to press TAB. After enter recipient, you need to press TAB 3 times to get into subject field, again TAB 4 times before you can start wring the message.
To get to compose, you need to click “New Item” then select “New email” from drop down menu. That is lot of wasted time on a Mail application where primary purpose is to sent and receive emails. It will be better to have a “Compose” or “New email” button like most other email providers, make easy for users.
I don’t think i can compare it with Google G Suite as it come with much more features like Google Drive, Documents and many more. But for business use, many of these may not required, it depends on the business.
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Install Docker on Ubuntu
To install Docker on Ubuntu, run
apt install docker.ioAdd your user in docker group
sudo usermod -aG docker YOUR_USER_NAMEBack to Docker
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portainer – Web based UI for Docker
Portainer is a web based UI for managing docker.
You can run it with command
docker volume create portainer_data docker run -d -p 8000:8000 -p 9000:9000 --name=portainer --restart=always -v /var/run/docker.sock:/var/run/docker.sock -v portainer_data:/data portainer/portainer-ceNow login to portainer with url
http://YOUR_SERVER_IP:9000
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swap
First create a 2 GB file
dd if=/dev/zero of=/swapfile bs=1M count=4096
For 8 GB, use count=8192. You can also use fallocate command instead of dd.
fallocate -l 8G /swapfile
Make it swap
mkswap /swapfile chmod 0600 /swapfile swapon /swapfile
Add it to /etc/fstab
echo "/swapfile swap swap defaults 0 0" >> /etc/fstab
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DNS Tools
Reverse DNS/rDNS/PTR Record
How to delete Google Cloud DNS ZoneDNS Tools
- https://dnschecker.org
- https://intodns.com
- https://dnsmap.io
- http://leafdns.com
- https://dnsviz.net
- https://www.dnsperf.com
- dig
- Google Public DNS Query Tool
- DNSSEC Debugger
- Find all sites using a specific nameserver
DNS History
- https://securitytrails.com/ – IP history
- https://completedns.com/dns-history/ – DNS History
DNS Propagation Checker
- https://dnsmap.io – check DNS propogation from differnt countries.
- Whatsmydns.net – check DNS propogation from differnt countries.
- https://dns.google – check DNS propogation from differnt countries.
DNS
- Free DNS Hosting
- Delegate a sub-domain to DNS server
- Find Reverse-DNS/PTR using dig, nslookup, host
- dnsmasq
- Install Cpanel DNS Only Server
- How to find all subdomains of a domain
DNS Resolver
- /etc/resolv.conf
- Ubuntu Configure systemd-resolved
- Public DNS Resolver
- Install Unbound DNS caching server
DNS Errors
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Apache Invalid command Header
On a new Debian server with Apache, web site give 500 internal server error.
On checking error log, i found
[Thu Jan 04 06:44:42.483932 2018] [core:alert] [pid 27583] [client 112.133.248.19:63020] /home/user/public_html/.htaccess: Invalid command ‘Header’, perhaps misspelled or defined by a module not included in the server configuration
The error is due to Apache headers module not installed on the server.
To fix, run
a2enmod headers
Restart Apache
systemctl restart apache2
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Radio
allow you to run your own radio station. It allow you to manage you media, playlists. It support IceCast and Shutcast as media servers.
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Ubuntu point all .test domains to 127.0.0.1
Until recently .dev was popular TLD used by developers for local web development. Recently google acquired the rights to use .DEV domain name extension and forced SSL for this LTD in google chrome.
Web developers are looking for alternate home for their local development web sites. Some suggested .localhost as development LTD, but it is too large. Another option is .test, this is a reserved LTD, so you won’t be forced to leave and is short. So many opted for .test as local development domain extension.
DNSMasq allow you to point *.test domains to 127.0.01, so you don’t have to edit /etc/hosts and add each domain you need for local development.
To do this, create file
vi /etc/NetworkManager/dnsmasq.d/test
Add following
address=/.test/127.0.0.1
Restart network-manager.
service network-manager restart
We restarted network-manager as dnsmasq is started by Network Manager.
root@hon-pc-01:~# pstree -sp $(pidof dnsmasq)
systemd(1)───NetworkManager(11557)───dnsmasq(11594)
root@hon-pc-01:~# -
certbot certificates
To list all letsencrypt SSL certificates, run
certbot certificates
Example
root@ok:~# certbot certificates Saving debug log to /var/log/letsencrypt/letsencrypt.log Revocation status for /etc/letsencrypt/live/boby.hosthat.com/cert.pem is unknown ------------------------------------------------------------------------------- Found the following certs: Certificate Name: boby.hosthat.com Domains: boby.hosthat.com Expiry Date: 2017-06-11 15:10:00+00:00 (INVALID: EXPIRED) Certificate Path: /etc/letsencrypt/live/boby.hosthat.com/fullchain.pem Private Key Path: /etc/letsencrypt/live/boby.hosthat.com/privkey.pem Certificate Name: img.serverok.in Domains: img.serverok.in Expiry Date: 2018-05-02 16:06:53+00:00 (VALID: 66 days) Certificate Path: /etc/letsencrypt/live/img.serverok.in/fullchain.pem Private Key Path: /etc/letsencrypt/live/img.serverok.in/privkey.pem Certificate Name: lab.hostonnet.com Domains: lab.hostonnet.com Expiry Date: 2018-04-25 03:34:37+00:00 (VALID: 59 days) Certificate Path: /etc/letsencrypt/live/lab.hostonnet.com/fullchain.pem Private Key Path: /etc/letsencrypt/live/lab.hostonnet.com/privkey.pem Certificate Name: yboby.cf Domains: yboby.cf www.yboby.cf Expiry Date: 2018-03-21 19:43:49+00:00 (VALID: 25 days) Certificate Path: /etc/letsencrypt/live/yboby.cf/fullchain.pem Private Key Path: /etc/letsencrypt/live/yboby.cf/privkey.pem ------------------------------------------------------------------------------- root@ok:~# -
Syntax error or access violation: 1071 Specified key was too long
When running database migration in a new larvel project, i get following error
boby@hon-pc-01:~/www/proxy (master)$ php artisan migrate
In Connection.php line 664:
SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes (SQL: alter table `users` add unique `users_email_unique`(`email`))
In Connection.php line 458:
SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes
boby@hon-pc-01:~/www/proxy (master)$
This is due to recent change in Lavral, that changed default charset to utf8mb4.
To fix this error, open file
vi app/Providers/AppServiceProvider.php
Find
use Illuminate\Support\ServiceProvider;
Add below
use Illuminate\Support\Facades\Schema;
Find
public function boot() { // }Replace with
public function boot() { Schema::defaultStringlength(191); }