The 150% BOM

Over the next couple weeks, I will be exploring the %150 BOM concept and how the concept can be implemented in ERPNext.

I recently encountered the “150% BOM” and had to look deeper.

The 150% BOM concept is a method of managing products that are essentially variations on a common theme, such as a car that is available pained either blue or red. You could manage the cars as completely separate products (albeit that share a lot of common components), but are truly different products. A 150% BOM includes all the variants of a product, from which specific BOMs – the 100% BOMs – are created.

Here is a simple 150% BOM for the marketing level of the SCC Aircraft Wireless product. Three different lengths for antenna and ground wires are provided in the BOM, and a specific length of must be selected to create an order.

 

 

Stay tuned, the next update will describe implementation options in ERPNext.

Install ERPNext on FreeBSD 11.2 using VirtualBox

Search for other ERPNext-related posts. You may also visit the demo on dalescott.net.

The simplest way to “install” ERPNext on FreeBSD is to simply use the Virtual Image provided by the ERPNext project with VirtualBox.

The ERPNext project provides the Easy Install script for bare-metal installation but it has a number of Linux dependencies and will not work without changes on FreeBSD. Happily, the project also provides a fully configured virtual machine (based on Ubuntu Linux).

It may also be possible to use bhyve, the BSD hypervisor, with the virtual image, but the OVF file must first be converted to bhyve’s raw format.

Install VirtualBox

Install the virtualbox-ose-nox11 package for running headless virtual machines.

% sudo pkg install virtualbox-ose-nox11

The VirtualBox kernel module (virtualbox-ose-kmod) will also be installed, but it must be re-compiled from source and re-installed (at the very least, the system will crash when next re-booted once it has been configured to load the kernel module at boot). 

Update the ports collection to prepare for compiling the kernel module. 

# portsnap fetch update

If the ports collection has not been installed, install.

# portsnap fetch extract

The FreeBSD sources are required to compile the kernel module. If not already installed, install the FreeBSD sources.

% fetch ftp://ftp.freebsd.org/pub/FreeBSD/releases/amd64/11.2-RELEASE/src.txz % tar -C / -xzvf src.txz

Compile and install the virtualbox-ose-kmod port. Make will first refuse to install the module because it is already installed (recall it was installed by being a dependency of virtualbox-ose-nox11). De-install the virtualbox-ose-kmod package, then re-install the newly compiled version.

% cd /usr/ports/emulators/virtualbox-ose-kmod
% sudo make
% sudo make install
% sudo make deinstall
% sudo make reinstall

Perform post-install configuration.

1) edit /boot/loader.conf to load the vboxdrv kernel module at boot,

# vi /boot/loader.conf
...
vboxdrv_load="YES"

2) increase AIO limits by editing /etc/sysctl.conf (my server is using AIO, for more information refer to the virtualbox-ose-nox11 pkg-message).

vfs.aio.max_buf_aio=8192
vfs.aio.max_aio_queue_per_proc=65536
vfs.aio.max_aio_per_proc=8192
vfs.aio.max_aio_queue=65536

Reboot the system to load the kernel module (or load it manually).

Make a mental note before doing an OS update to first edit /boot/loader.conf to not load the module. Otherwise the system will likely crash when next rebooted.

The user that VirtualBox runs as must be a member of the vboxusers group. For simplicity, I’ll run VirtualBox using my own username, although best practise would be to create a dedicated user.

# pw groupmod vboxusers -m dale

Edit /etc/rc.conf to run vboxwebsrv (the Virtual Box web interface daemon) using the provided startup script installed in /usr/local/etc/rc.d/

% sudo vi /etc/rc.conf

vboxwebsrv_enable="YES"
vboxwebsrv_user="dale"

and finally start the vboxwebsrv service.

% sudo service vboxwebsrv start
% sudo service vboxwebsrv status

The vboxmanage cli utility can be used to manage virtual machines but I will be using phpVirtualBox which provides a familiar GUI.

Install phpVirtualBox

phpVirtualBox can be installed from the FreeBSD ports collection but it currently has a dependency on PHP 7.1 while I have PHP 7.2. I installed phpVirtualBox manually to avoid pkg attempting to revert my PHP install to 7.1, and have not encountered any issues.

Download the latest release from the phpVirtualBox Github project . Follow the instructions in README.md file and on the wiki. Extract the project to /usr/local/www, and edit the configuration.

# vi /usr/local/www/phpvirtualbox/config.php

var $username = 'dale';
var $password = 'dale_login_password';

Configure the webserver to serve phpVirtualBox. I’m using the basic Apache 2.4 http server package. I added a virtual host definition to /usr/local/etc/apache24/extra/httpd-vhosts.conf to serve phpvirtualbox as a phpvirtualbox.dalescott.net.

<VirtualHost phpvirtualbox.dalescott.net>
  DocumentRoot "/usr/local/www/phpvirtualbox"
  <Directory "/usr/local/www/phpvirtualbox">
    allow from all
    Options None
    Require all granted
  </Directory>
</VirtualHost>

Change the default phpVirtualBox login password to something secure after logging in for the first time.

“Install” ERPNext

Download the desired ERPNext Virtual Machine image (*.ova).

% cd ~/downloads
% wget http://build.erpnext.com/ERPNext-Production.ova

Using phpVirtualBox, create a new vm by importing the downloaded ERPNext-Production.ova Virtual Image file (File/Import). The OVF includes port forwarding rules to forward client port 80 to host port 8080 (for serving ERPNext) and a rule to forward ssh from client port 22 to host port 3022 (for system administration).

Start the vm and then login to ERPNext from a browser (e.g. www.dalescott.net:8080) using the default credentials. The new site wizard will run and lead you through ERPNext configuration. Use a secure password when defining the initial (admin) user, and the wizard will delete the initial Administrator user (with default password) when complete. 

Once logged into ERPNext, setup email processing so that users will receive notifications outside of ERPNext. This will be valuable to understanding and appreciating ERPNext’s significant social aspect. You will also want to change the system login (i.e. ssh) password for “frappe” user to something secure (or disable password authentication entirely in favor of key-based authentication).

Cheers,
Dale

 

PLM using Parts&Vendors

Parts&VendorsTM was the seminal multi-user application in the late 90’s for embedded-electronics design teams to manage parts and assemblies. Running on Windows 98SE (originally), Parts&Vendors managed everything to do with embedded product development, including tracking parts, vendors, manufacturers, purchasing, supporting documents, and even rudimentary stock control for low-volume manufacturing. Teams worked efficiently with more cooperation, less bureaucracy, and at much lower cost, than possible with other solutions of the time.

Parts&Vendors was discontinued in January 2014, almost 15 years after it was released IMHO due to insurmountable technical debt. The Jet-type database did not handle clients crashing or high WAN latencies gracefully, and the codebase had not kept pace with Windows development practices.

Although no longer available, Parts&Vendors remains useful as a gold standard for evaluating PLM capabilities of ERP systems, such as ERPNext and webERP.

Parts&Vendors UX / UI 

Item Master Tab

Parts are accessed through the Item Master tab.

Item Details

Selecting a part provides detailed information on sources (vendors) as well as other useful information.

Files and URLs

Documents and web sites can be associated with a part,

making it easy to access local documents or a web page for reference.

Unfortunately PV did not include a document control user interface to keep things in order, or utilities to verify document paths or list parts referencing a particular file. The shared directory approach worked well for a small conscientious team, or one with a dedicated “librarian”, but not with a more “entrepreneurial” team (if you know what I mean <wink>).

Assemblies

A part may be grouped with others in an Assembly. You can easily tell what assemblies include a particular part in PV from the part’s Used On tab. 

It’s also easy to navigate from a part to a containing assembly, and back. This is also called traversing a product tree containing child parts and parent parts.

An assembly has a Parts List (aka Bill-of-Materials or BOM) that lists its child parts.

Purchasing

Parts can be easily ordered,

An order can accumulate parts until it is placed with a vendor, eventually resulting in a purchase Purchase Order (PO).

In a smaller organization, the engineering team often does the ordering themselves. In a larger organization, a “real” purchase order may need to be created in a separate parallel system (e.g. QuickBooks). The exact process will depend on an organization’s size, structure, and history.

Receiving

When the ordered parts arrive, the PO is retrieved and the order item marked received, 

which updates the stock on hand.

The assembly Parts List is one way to see when the parts necessary to build an assembly are in stock.

Manufacturing

Once all the child parts for an assembly are in stock, a “Kit List” is generated from the “Build” tab for manufacturing. Stock on hand can be reduced for the kitted items, and later increased for the finished assembly when completed. 

Customers

PV can also manage clients and client orders, although the functionality is not integrated with stock control and closing an order does not reduce quantity on hand of the ordered items. The functionality is understandable though given it was never a goal of PV to be a POS (Point Of Sale) or CRM (Customer Relationship Management) system. 

 

This completes a quick refresher of Parts&Vendors. In the next post I will compare ERPNext to Parts&Vendors.

ERPNext Change Management

I followed a defect report through the ERPNext change management process to understand the process. Nice job guys!.

The issue had to do with the Service Provider Chapter member listings on erpnext.org. John Clarke, the chapter leader, created an issue in the erpnext project repo on Github using screenshots I made.

 

Next, back at ERPNext headquarters in Mumbai, a developer named Vishdha assigned the issue to himself. He also left a record showing the incorrect data had been removed from the production site database.

Nabinhait, a senior developer, added the issue to the January 2018 milestone (implying a monthly cadence to releases). Vishadh found the issue had been corrected in a pull request he issued two weeks ago (but obviously not yet pushed to the production site). Leaving a trail for others to follow, Vishadh added a reference to the issue in the pull request, and cross-referenced the pull request in the issue.

Following trail from the issue to Vishdha’s Pull Request, the pull request is comprised of changes to 7 files in four individual commits.

Reviewing the individual commits,

we can drill down one final level to see the actual changes Vishdha made in each file. 

However, although a fix was committed to the erpnext code repository two weeks ago, it’s clearly not yet on the foundation server (erpnext.org).

Vishdha wasn’t finished yet though and submitted a pull request to add the fix to the non_profit domain, which was subsequently merged into master by nabinhait which then officially closed the issue.

Trusted and Transparent. Nice work!