Author: flipaoXIX

Dune4: God Emperor of Dune

I had low expectations in this book after reading the third part. But I was surprised at the beginning about the new setup of the planet, Leto and new twists. The “philosophical” moment of Leto are a bit boring because I got to the point I dont know what he is talking about but I liked when he mentioned Torquemada when discussing about religions. The end of the book wasn’t really great but I enjoyed it overall. Looking forwards for the next chapter!

Squid Ink Pasta

I had squid ink leftover and while on holidays I saw in a restaurant a dish of squid ink past that looked very good so I decided to try. And this video looked like a good recipe.

Ingredients for pasta:

  • 100g 0.0 flour
  • 1 free range egg
  • 1 tbs squid ink for pasta

Process for pasta:

  • In a crystal bowl, make a heap with the flour and then a hole in the middle where you crack the egg and add the ink
  • With a fork start mixing the egg with the flour from inside the circle to the outside.
  • In a work surface, cover it if you can with baking paper, and knead the dough. Keep in mind this can stain your surface kitchen and/or your hands.
  • Knead until smooth. Dont add flour.
  • Cover the dough with film and let it rest for 30 minutes
  • Rolling the pasta manually is quite hard. Use a rolling spin and flour. Try to flat as much as you can the dough.
  • Once it is spread enough, with a shark knife try to make spaguetties.
  • With plenty of flour to avoid to dry out, leave the pasta in a tray.

Very thick pasta 🙁

Ingredients for sauce

  • 1 can of tomate sauce
  • 1 onion chopped
  • 1-2 gloves of garlic
  • drizzle of white wine
  • 2 tbs squid ink
  • 400g frozen squid

Process for sauce

  • In a hot pan with a gulp of olive oil, cook the onions
  • Add the minced garlic and cook with onions. Avoid burning them!
  • Add squid. Cook it through!
  • Add a splash of wine
  • Add the tomate sauce and stir
  • In a pan with boiling water, put the pasta for 90sec.
  • Add squid ink to the tomate sauce and mix
  • Add the pasta and a bit of pasta water in the tomate sauce
  • Mix all well.
  • Ready to serve!

To be honest, my pasta was too thick 🙁 but it was tasty enough. I dont cook homemade pasta too often so maybe it is one of the reasons. I dont want to buy another machine just for pasta though.

Anyway, it was nice to try!

Granola Bar

I was looking for a homemade snack bar and this video with a good one.

Ingredients:

  • 1 cup of nuts, chopped (any type)
  • 2 cups of oats
  • 1 cup of tahini
  • 1/4 cup maple syrup
  • 1 tbs of vanilla paste
  • 1/2 cup of coconut shreds
  • 1/4 cup of cranberries or peel fruit (optional)

Process:

  • Prepare a small tray with baking paper
  • Mix tahini, maple and vanilla in a bowl
  • Add oats, nuts, coconut and cranberries. Mix all well
  • Pour mix in tray, spread it evenly.
  • Chill in fridge for 1-2h (better freezer)

To be honest my first attempt was quite bad as I didnt have enough tahini.

The second one was a bit better but doesnt look very “solid” like in the video. I think I need to try the freezer.

Tastes good and is not very sweet. Doesn’t feel like chewing sugar.

Essentialism

This is a book about “simplifying” your life, removing what is not necessary and focus in the important. These are nice words but actually very difficult to accomplish nowadays. I have read several book that are quite related to this subject, like “indistractable”, “drive”,”deep work”, “flow”, “atomic habits”, etc. Focus in “less is better”. If you dont put a limit, somebody will do it for you

For me, I am struggling in the “Tech” side. I want to learn so many things that at the end of the day/week/months/years I notice I haven’t reached anywhere. I have hundreds of tabs open in my browser with things I want to read “soon”. Something similar happens with recipes, I have so many pieces of magazines, videos and pics in my phone, that I feel overwhelmed. At least I am focus in my climbing (getting fitter), baking (bread!)/cooking and reading.

The author explains the process to become an Essentialist as three phases:

Explore:

  • Create space. It is good to be bored. Read old books. Meaning.
  • Play: Sir Ken Robinson
  • Sleep: Protect the most important asset, you!
  • Select: Hell yeah or no. Trade-offs. Good to Great (book).

Eliminate

  • clarify: cleanup the wardrobe
  • dare: say “no”
  • uncommit: sunk cost, endowment effect, fear of missing out
  • edit: options, condense
  • limit: you can pay a price for setting boundaries BUT boundaries are freedom!

Execute:

  • Buffer: add 50% in your planning. extreme preparation
  • Substract
  • Progress: repeat, repeat
  • flow: create routines

This is the typical book that I put in my stack of good reads, to read again at some point so I can refresh concepts because I forget things. Even after finishing it a couple of days ago, I got the feeling that I have forgotten most of it. And in this case, I gave away the book so I am even struggling to get my notes/thoughts here 🙂

Pandas

This is something I have heard about in the past but never used. So this week, as finally decided to write a script to help me to find the peers of flapping ports, learned about pandas from first time. I used another script as “inspiration” and after seeing it was using pandas, I decided to read a bit about it and give it a go.

The main type is the DataFrame. In my head, pandas is just a library to deal with CSV, spreadsheets, etc like when you use a program like libreoffice. And this page, gave me the hints for creating the query I wanted to make.

So at the end I have my very basic script but saves me time logging to each device and find the peer port.

Of course, there are different ways to tackle this problem, but in my environment, the source of truth for links is in a file. You could have that info in the port description too, or in a database, etc.

$ python3 flapping-peer.py -f flapping-list.txt

Result:
SW1 Ethernet1/1 SW2 Ethernet1/1
SW1 Ethernet1/4 SW2 Ethernet1/4

$  
$ cat flapping-list.txt 
SW1,Ethernet1/1
SW2,Ethernet1/4
$
$ cat patching-file.csv 
Site,Source Device,Source Interface,Destination Device,Destination Interface,Media
A,SW1,Ethernet1/1,SW2,Ethernet1/1,SMF
A,SW1,Ethernet1/2,SW2,Ethernet1/2,SMF
A,SW1,Ethernet1/3,SW2,Ethernet1/3,SMF
A,SW1,Ethernet1/4,SW2,Ethernet1/4,SMF
A,SW1,Ethernet1/5,SW2,Ethernet1/5,SMF
$

TCP Asymmetric

I got escalated an issue recently that had caused several outages and needed an urgent fix.

For different reasons, we had asymmetric routing in SITE-A. The normal flow is the green arrow. During the asymmetric routing, the flow is the red line. Routing wise, things should work. BUT, we have firewalls in the path. The firewalls were configured to allow asymmetric connections (I was told). As far as I could see in the config and logs, nothing was dropped in the firewalls during the issue.

So first thing, I fixed the asymmetric routing so it didnt happen again. I took me a while to come up with the solution (and it was quite simple) as I had to understand properly the routing before and during the issue. The diagram is quite simplified at the end of the day.

So during the maintenance window when I applied the fix for the asymmetric routing, I managed to take some traces in the firewalls, as I was trying to understand where the traffic was dropped/lost during the asymmetric scenario. As well, I was not very familiar with several parts of the network and the monitoring, I didnt know which links where already tapped or not. Once I was happy with the routing fix, I tried to take a look at the traces. At high level, I could see the return traffic leaving FW1 and leaving DC1-SW1. Based on that, I started to think that the firewalls were fine…..

In another maintenance, I tried to take more logs in different part of the network and I could see clearly the traffic reaching A-SW1. As I ran of time and missed to tap some links, I couldnt carry on.

So based on the second maintenance, the issue had to be inside SITE-A. Somehow it didnt make sense. I checked I didnt have uRPF enabled. The rest was pure L2 so it couldnt see the L3…

So in the third maintenance, I got all my debugging tools to verify that any network kit was dropping the traffic in SITE-A…. and it was useless. I realized that I could do a tcpdump in the client IP1 i was using for testing and I could see some return traffic!!!!

So, I was just socked. I didnt get it. It didnt make sense.

Somehow, I reviewed the tcp captures I was doing in each interface of both firewalls. I was trying to get to basics.

I was assuming the TCP handshake was completed properly. After paying a bit of attention to the client logs… I could see the TCP handshake completed. And I could see the HTTP GET getting to and leaving DC2-FW…. so why the server IP2 was not answering!!!!???

So back to the tcp handshake and firewall captures, I was comparing step by step. Somehow, I missed that the TCP ACK from client IP2 was reaching DC2-FW…. but it was not leaving DC2-FW!!!! even worse, the HTTP GET it was actually crossing the DC2-FW !!!

SLAP IN THE FACE!!!

This is the TCP handshake. This is networking 101…..

The TCP state-machine in client and server during the asymmetric scenario

So I was asumming that because the client was sending HTTP get, the tcp handshake was completed in both ends!!!!

It didnt make sense why I was seeing TCP SYN-ACK retransmissions from the server IP1…. BECAUSE the TCP ACK from client IP2 never reached.

For that reason server IP2 never answered the HTTP GET, because from its end the tcp hanshake was not completed.

I banged my head several times on the table. I “saw” this during the first maintenance window when I took the tcpdump in the firewalls BUT I didnt pay attention to the basic details.

I trusted too much to see a wireshark trace because it is more visual and shows more info but the clues were all the time in the tcpdump from the firewalls that I didnt bother to pay full attention.

At least, I found out where and why the connections failed during the asymmetric routing scenario. A firewall upgrade did the job.

So all fixed.

Lessons learned:

  • without proper foundation, you can’t build knowledge (tcp handshake state in client and server)
  • when things dont make sense, get back to basics (tcp handshake)
  • get the most of the tools at hand (tcpdump – PSH packets were the HTTP GET !!!!)

Sourdough Focaccia (II)

I tried some time ago sourdough focaccia but I wasnt really happy with the result and somehow found this video and decided to try again.

Ingredients:

  • 320g water
  • 100g sourdough starter
  • 400g strong white flour
  • 15g olive oil
  • 8g salt
  • 15g oil + 15g water
  • toppings: sliced onion, cherry tomatoes and slice green/black olives
  • salt, pepper, herbs

Process

  • Add the active starter to the water, mix well
  • Add flour and oil, mix a bit.
  • Add salt and mix well.
  • Cover it and let it rest for 30 minutes.
  • Make 1 fold
  • Cover and let it rest again for 30 minutes
  • Make 1 fold
  • Cover and let it rest for 2-3h.
  • Make a “coil” fold
  • Cover and let it rest in the fridge overnight (12-14h)
  • Take the dough out of the fridge. On a lightly dusted table top, shape the dough, trying to keep as much air inside (most difficult part for me)
  • Oil a pan and put the dough on it. Let is rise for 3h
  • Pre-heat oven at 230C
  • Mix oil + water. Pour on the dough and with clean hands, make pockets with your fingers.
  • Fill the pockets with your toppings (onion, tomatoes and olives)
  • Add some salt, pepper and herbs of your choice (oregano, basil, rosemary, etc)
  • Bake for 25 minutes or till the top is crispy at 230C.
  • Remove from oven and let it cool down

This is the result!

whole foccacia

sliced foccacia

It was very tasty, spongy and moist. Not as much open crumb like the video but really happy with the result!

Foundation’s Edge

This is the forth book of the series. I was a bit weary at the beginning as I thought it was going to be a boring continuation (like it was my last Dune book). But it hooked me and read it voraciously. I was surprised how quickly I finished it. I liked how all the parts are faced at the end and the goals they want to achieve plus how different are the personalities of each character.

It was interesting after four books, that is the first time it is mentioned alien life and robots. Thinking this is sci-fi based on a very far future I should have noticed that very early on the series but still it is really engaging with all the twists.

Looking forwards for the next books!

Attached

This book was a gift from a very good friend. It has been an interesting read as it has helped me to put labels to my own behaviours and explain some situations in my last (and only) relationship.

The book states there are mainly three type of behaviours in relationships

  • Secure: comfortable with intimacy and communicating.
  • Avoidant: dont want to get to close for fear to lose independency
  • Anxious: too preoccupied and overthinking the relationship, requires lot of closeness.

In my case I am mainly avoidant, and I realised that my ex-girlfriend was anxious. And funny enough, it seems the statistics say this is the common common couple because there are few “secure” in the market and relationships between members of the same group are really uncommon. I actually laughed at this! But I think it is quite true.

The goal is not becoming overnight a secure person but to communicate needs from each side to make the gap smaller.

And from other side, people evolve, change for good and bad. So if you are secure doesnt mean you are always going to be secure, if you attachment fires in a weird way to you can end in a bad situation.

While reading this, I was analyzing myself and my former relationship and was funny how many things started to make sense.

Another thing, attachment is not love. That was a relief. Before my former relationship, I got hit by another person and that made me feel like a puppet, I felt like nothing and I hit rock bottom. But that helped me to work on myself seriously. And this can happen to anybody…

And bad attachments can be difficult to break…

Although, this is not just extremes. I think I have been secure in several points but now I have understand myself better and I think I would act better in a new relationship.

As well, this knowledge helps you to filter potential partners or actual ones. So it can help you to improve your relationship.

At the end of the day, (as usual, I am always trying to find the universal truth in books), everything is reduced to communication. Express your needs openly. Make the relationships a two way street that goes to places.

Arroz Negro

This is a dish that I thought I would never taste neither cook as always saw it with more than squid. Until I went to Galicia with friends and one day we ate arroz negro in a restaurant. I didnt see anything that could give me an allergic attack, although I wondered later on the day if they had used fish stock… but I survived 🙂

So based on that experience, I decided to try it myself at some point. And that was today. I found a video that matched my expectations of using only squid. I bought a couple of things I missed (nothing special) and already had the squid ink I bought online.

Ingredients:

  • 400g frozen squid rings
  • 1-2 tsp of squid ink (or more)
  • 1 bunch of spring onions chopped
  • 1 pepper chopped: I used an orange one.
  • 2 cloves of garlic chopped (I forgot to add it!)
  • 2 tsp of tomate paste
  • 500m of boiling water with a vegetable stock cube
  • 200g aprox (or a bit more) paella rice
  • 1-2 tsp of turmeric
  • salt

Process:

  • In a hot paella dish, drizzle a bit of olive oil. Add the frozen squid rings. Add a pinch of salt.
  • Keep stirring until you have crust in the bottom of the dish. Not burn!!! Drop the heat to medium-low.
  • Add the spring onions and pepper. Mix continuosly, dont allow to burn!
  • Add the tomate paste and mix.
  • Add the rice and mix well for 1 minute or so. Dont allow to burn!
  • Add the vegetable stock with the boiling water. Add a pinch of salt.
  • Add the squid ink with a bit of boiling water to be sure it is not solid.
  • Be sure the paella dish is completely black (In my case I should have added 1 more tsp of ink)
  • Add the turmeric and mix. Taste it! Dont move the rice any more after this.
  • Increase heat to high for 5 minutes aprox. Be sure you move the paella dish to be sure the heat is spread out evenly so the rice is cooked everywhere.
  • Drop the heat to medium.
  • Wait until most of the water is evaporated. With a tsp, try a bit of the rice to be sure it is cooked. You should be able to scratch the bottom and get the extra flavour!
  • Remove from heat, and let it cool for a minute. Ready to eat!

Garlic Mayo

  • 200ml sunflower oil
  • 1 egg
  • 2 chopped garlic cloves
  • salt
  • 1 tbsp of vinegar
  • 1/4 lemon juice

Process:

  • Put all ingredients in a tall glass and use a hand blender.
  • Blend and taste! Need salt? Lemon?
  • Put in a bowl and to the fridge

For my first time, really happy, better than I expected! Just add more ink next time 🙂