In 2016, I came across a nice deal for an on-ear headphone – The Motorola Tracks Air. It was selling on Flipkart for ₹2500. That was steal deal, considering the original price is ₹8990. I used it for on and off for quite some time but the on-ear type meant it started hurting my ears when using them for more than 30 minutes. So gradually the usage waned off and I stopped using it. Usually I do not buy new stuff unless the previous one I have is completely dead, this is especially true in case of electronics. Because of the online shopping deals it’s very easy to accumulate unnecessary junk. Just like that due to impulsive purchases without much thought I have a few electronic junk lying around which is in pristine condition not used even a single time.
In order to get rid of the Tracks Air headphones which I had, I tried putting an ad for it on OLX India site which is a famous marketplace for pre-owned stuff. I have successfully sold quite a lot of things on the platform and even bought a few. But for some reason people didn’t seem to be interested in this headphone at any price, so I gave it to someone I knew and didn’t have any headphone for free. At least something lying in my junk is useful to someone.
Maintain lead acid batteries regularly
Thursdays are usually maintenance day for the electrical power supply company in my area. So there was nearly a full day power cut. Luckily, I have a UPS so that sorts out the problem for 8-9 hours. The lead acid battery I use for my UPS is about 3-4 years old, and these being unsealed batteries they last long, really long if maintained properly.
In the past I have had one such battery last for a decade before requiring a replacement.
Unsealed lead acid batteries require two important maintenance activities:
- Topping up distilled water every 6 months
- Applying petroleum jelly / grease on the terminals to prevent corrosion
Tree plantation – Wild Almond
Tree plantation has always been a thing I wanted to do & has been in my to-do list for the last couple of years. This year I started with the first tree, a Wild Almond. Somebody gifted it to my mom on World Environment Day, 5th June 2019.
Here’s how it looks as before and after plantation:
There were little bit of pre-monsoon showers yesterday evening so the soil was a bit soft, but there were lot of stones underneath, my Khurpa (the weeding tool) has it’s nose bent due the impact against stones while digging.
Continue reading “Tree plantation – Wild Almond”When you get blocked on social media (Twitter) for defending Yoga
In the world of Twitter I came across an interesting thread, discussing morning affairs that every human being has to go through:
I thought it would be a good idea to pitch in with my limited yoga knowledge because yoga has helped me in that morning affair as well:
To that, this person @abhijitkadle says he wants to see scientific basis or else it is bullshit:
I have experienced a lot of health benefits due to practicing yoga over the years compared to when I was not. Alright, so I started replying to this thread with various links and articles which had the appropriate references to some studies and papers by prestigious institutes. Let me share the links I have shared with Mr. Prometheus lapetus on the thread one by one and the referring research papers each of the link(s) had.
Continue reading “When you get blocked on social media (Twitter) for defending Yoga”Ubuntu 18.04 add e1000e Intel driver to dkms
e1000e is an Intel NIC driver which often needs to be updated on servers so that the NIC can operate trouble free.
Note: I assume you have DKMS and the necessary kernel headers to compile the drivers already installed. If not use apt / apt-get to install the same.
Here’s a quick guide on how to add the Intel e1000e driver to DKMS (Dynamic Kernel Module Support) so that it gets installed / uninstalled automatically with future kernel updates and removals.
Download the driver from Intel website https://downloadcenter.intel.com/download/15817
As of my writing this article, the e1000e version is 3.4.2.1. On download the tarball I get e1000e-3.4.2.1.tar.gz.
Extract it to /usr/src:
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tar -xzf e1000e-3.4.2.1.tar.gz -C /usr/src |
Create a dkms.conf in /usr/src/e1000e-3.4.2.1 with following contents:
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PACKAGE_NAME="e1000e" PACKAGE_VERSION="3.4.2.1" AUTOINSTALL=yes MAKE[0]="make -C src/" BUILT_MODULE_NAME="e1000e" BUILT_MODULE_LOCATION="src/" DEST_MODULE_LOCATION="/kernel/drivers/net/ethernet/intel/e1000e" |
Next, we have to tell DKMS that such a module has been added and build it for each of the kernels we have on the system:
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dkms add -m e1000e/3.4.2.1 for k in /boot/vmlinuz*; do dkms install -k ${k##*vmlinuz-} e1000e/3.4.2.1 done |
Finally, reboot the system and the new module should be live.
Date range in a MariaDB query using the Sequence Engine
One of my applications involved generating a date-wise report for items created on that day and we needed zeroes against the count of items on the date which had no entries.
User selects a date range and the application must generate this report. Not so easy if I had not come across the MariaDB Sequence Storage Engine!
Sequences have long been good features in databases like Oracle, PostgreSQL and the likes, I absolutely had no idea of it’s existence in MariaDB — just came across it while browsing the documentation of MariaDB.
Here’s a sample of my use case:
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MariaDB [test]> create table items (id int unsigned primary key auto_increment, date_created datetime not null); Query OK, 0 rows affected (0.061 sec) MariaDB [test]> insert into items (date_created) values ('2019-01-01'), ('2019-01-05'), ('2019-01-06'), ('2019-01-06'), ('2019-01-01'), ('2019-01-10'), ('2019-01-09'), ('2019-01-09'), ('2019-01-09'); Query OK, 9 rows affected (0.032 sec) Records: 9 Duplicates: 0 Warnings: 0 MariaDB [test]> select * from items; +----+---------------------+ | id | date_created | +----+---------------------+ | 1 | 2019-01-01 00:00:00 | | 2 | 2019-01-05 00:00:00 | | 3 | 2019-01-06 00:00:00 | | 4 | 2019-01-06 00:00:00 | | 5 | 2019-01-01 00:00:00 | | 6 | 2019-01-10 00:00:00 | | 7 | 2019-01-09 00:00:00 | | 8 | 2019-01-09 00:00:00 | | 9 | 2019-01-09 00:00:00 | +----+---------------------+ 9 rows in set (0.001 sec) MariaDB [test]> select date(date_created), count(id) from items group by date(date_created); +--------------------+-----------+ | date(date_created) | count(id) | +--------------------+-----------+ | 2019-01-01 | 2 | | 2019-01-05 | 1 | | 2019-01-06 | 2 | | 2019-01-09 | 3 | | 2019-01-10 | 1 | +--------------------+-----------+ 5 rows in set (0.001 sec) MariaDB [test]> |
After a couple of attempts with the samples provided in the MariaDB documentation page, I managed to devise a query which provided me exactly what I needed, using SQL UNION:
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MariaDB [test]> select dt, max(cnt) from ( select cast( date_add('2019-01-01', interval seq day) as date ) dt, 0 cnt from seq_0_to_11 union select cast( date(date_created) as date ) dt, count(id) cnt from items where date(date_created) between '2019-01-01' and '2019-01-11' group by date(date_created) ) t group by dt order by dt; +------------+----------+ | dt | max(cnt) | +------------+----------+ | 2019-01-01 | 2 | | 2019-01-02 | 0 | | 2019-01-03 | 0 | | 2019-01-04 | 0 | | 2019-01-05 | 1 | | 2019-01-06 | 2 | | 2019-01-07 | 0 | | 2019-01-08 | 0 | | 2019-01-09 | 3 | | 2019-01-10 | 1 | | 2019-01-11 | 0 | | 2019-01-12 | 0 | +------------+----------+ 12 rows in set (0.001 sec) |
Yeah, that’s basically filling in zero values for the dates on which there were no entries. Can this be done using RIGHT JOIN? I tried to but couldn’t form a JOIN condition. If you know drop a comment!
Multi-WAN DNS in pfSense
Update: I later figured out there are many other places pfSense restarts Unbound, so this is simply not worth the effort. I reversed the changes & moved Unbound to another box and using just DNS forwarder on pfSense — which is used by the Unbound server.
Having multiple broadband connections at home, I have a pfSense which takes care of load balancing and firewalling. pfSense is pretty good in almost everything, except one thing that was annoying me a lot — That it restarted the DNS Resolver (Unbound) every time either of my WAN connections restarted (one of my ISPs restarts the connection periodically), and the traffic originating from the box itself cannot be load balanced across multiple connections due to a limitation in FreeBSD’s implementation of pf itself – it is unable to set the correct source address.
It’s quite annoying that – even when you use the forwarding mode of Unbound, your DNS still goes through a single WAN interface. Moreover, Unbound doesn’t seem to do parallel querying across DNS servers. So if you have listed multiple DNS servers as forwarders it will try them one by one as they fail. Suppose, the WAN interface from which DNS traffic is outgoing is running at full capacity – a download or somebody is streaming a video, then your browsing becomes slow as well – but the browsing itself may go through another WAN connection. Notably, for having a stable multi-WAN setup in pfSense – you have to use forwarding mode. The gateway switching for the box itself doesn’t work reliably in my experience, due to which I’ve had to face “host not found” error messages even when one of the connections was up.
The sad state of social media support among Indian companies
Use of social media by Indian companies have skyrocketed in the recent years due to many reasons, two to be specific –
- It helps people connect directly with government – a lot has been done in this regard under the Digital India initiative.
- Since social media is a public space, brands / companies are pressurized to correctly resolve the issue or it is a ticking time bomb for them in case the problem becomes viral, can damage reputation easily.
Now coming back to the support brands on Twitter, an example here:
BSNL is a telecom operator in India, and they have a Twitter account where they answer queries. My query was pretty simple – BSNL announced availability of 4G uSIMs nationally so I asked them if 4G service is available in Pune. Their response as seen above – they want contact details from me. Moreover, the reply says “Sorry for the inconvenience caused”. I didn’t face any inconvenience here. It’s just out of context! Why not just reply to the tweet with a simple yes or no? It doesn’t contain any private information.
Many such countless examples can be seen on the Tweet with replies page of their twitter profiles. Interestingly it’s a common trend, and I don’t know why. If you look at the twitter profiles of some international brands – they don’t reply in similar fashion, except in cases where private information (account number, mobile number, etc.) is involved.
Common general information can be shared publicly, no? If information involves private matters such as – someone has a specific problem for which details are needed – that conversation can happen in private.
History repeats itself – RSS and Blogs making a comeback?
Unless you’ve been sitting under a rock for the past couple of weeks, you would be well aware of the Cambridge Analytica scandal that happened with Facebook. Around the same time, I came across an article on Twitter – the source for all the content I read, which says It’s Time for an RSS Revival. I wasn’t using Facebook much and this news has pushed me even farther from it. There are specific reasons I am still on Facebook but my activity has reduced significantly.
Ever since Google Reader was killed, I had been using this RSS reader called NewsBlur. But I was already significantly into using social media as a source of new content, so I never really used Newsblur seriously – in spite of me having a premium account all these years.
Continue reading “History repeats itself – RSS and Blogs making a comeback?”