Review: High School Fleet

Overall rating: 9
This review will contain spoilers in regards to some of the main plot points of the show. You have been warned!

Wait a moment. High School Fleet? You mean to tell me, there is yet ANOTHER anime with girls and warships? I have no idea how this slipped past my attention, but it seems to be Girls und Panzer-esque, except in warships instead of tanks. So being a fan of the likes of Apreggio of Blue Steel, Kantai Collection, and the aforementioned Girls und Panzer there was no way in hell I was not going to watch this.

I honestly came expecting a anime where cute girls do cute things , but I was surprised by the way it ended up being and honestly it surpassed my expectations. And I'm glad that is not slice of life show that I was expecting because that made it even more interesting.

The series starts off quickly and reveals that a girl named Akeno Misaki (nicknamed “Mike”) with a big dream. She enrolls at an academy known as “Yokosuka Girls' Marine High School” with the goal to join the Blue Mermaids. For the first episode, the show establishes that Akeno and her crew faces unexpected circumstances as they are accused of mutiny. Furthermore, Akeno becomes the captain of the destroyer ship Harekaze. Make no mistake though, the show has a rather serious vibe despite the misleading atmosphere. The crew faces against battleships armed with real firepower capable of destroying them. Furthermore, Akeno is a newbie with lack of experience and tries hard to earn the respect of her crew. In essence, the show makes it clear that it’s no joke and pushes the idea of naval warfare to a level that you may not be prepared for.

As for the characters, individually, they don’t appear to be all that special, but as a whole, the cast turned out to be pretty decent.

(from left to right) Mei, Shima, Kouko, Wilhelmina, Rin, Mike, Isoroku, Mashiro, Akane, Homare, Maron, and Kaede
“Decent” is probably the best compliment I can come up with for Mike, who’s one of those protagonists that I generally don’t enjoy very much. She’s your every girl who winds up being the captain of the Harekaze, a smaller ship that’s home to a ragtag group of girls that weren’t thought of very highly. At times, she’s pretty inept in her leadership role, with Mashiro being much more fitting for the role of captain, yet this was one of those instances where a bland character gets outshined by several girls with lesser roles.

Among the crew, there is a variety of characters. One thought that crossed my mind is how the show can fit characterization with so many. After all, introducing all the girls at once seems like a mistake because there’s nothing in particular that makes them stand out individually besides the main protagonists. Most of them seems to have generic characteristics as well ranging from being stubborn, class clown, nervousness, etc. It’s also hard to ignore the similarities between this and Girls und Panzer especially with how talent is developed from both series. In some ways, the show does a neat job at making each episode relevant with its premise. In other ways, I have to say that the character cast is perhaps just too big for its own good.

Wilhelmina immediately comes to mind, as the German beauty eventually finds herself aboard the Harekaze after the shit hits the fan on board her own ship. If I could’ve had my way, I would’ve traded Mike for Wilhelmina, with Mashiro assuming the role of captain of the Harekaze, but that would’ve made too much sense. 😛

Maron and Kouko also left favorable impressions, and while Kouko had plenty of brief moments throughout the series, Episode 10 saw Maron shine as the person in charge of the Equator Festival. That was mostly a filler episode that gave us a lot of slice of life moments, yet it was fun nevertheless, thanks in large part to Maron. Oh, and there’s a cat that I liked better than some of the characters… 😀

Either way, you’ll probably find some characters from the series to be more noticeable than others. Besides Akeno, we have Mashiro Munetani, the deputy captain of Harekaze. Unlike Akeno, she seems more like the serious type that takes everything a bit too straightforward and even has a case of allurophobia. Then, there’s quiet girls like Shima Tateishi with elite gunning skills, Mei Irizaki with her passion to fight, Kouka Nosa with a theoretical mind, and timid Rin Shiretoko with decent steering abilities. They make up the bulk of the characters’ screen time so keep in mind while watching their roles. What I also find insightful about the show is that it divides the Blue Mermaid crew well with division to make each of them unique. For instance, there’s the Bridge of the crew with their central command objectives, the combat unit with their fighting talents, navigation division with their abilities to navigate under any circumstance, engineering department for construct and repair, and Logistics for aid in operations. The point is that the show doesn’t neglect any part of the Blue Mermaid crew and makes each role important to ensure the team’s success. On the downside, there isn’t much concrete characterization. The sheer amount of characters for this one cour show just seems a bit too much and perhaps the most characterization we’ll get is between Akeno’s childhood with her friend.

Between the story and the slice of life feeling, High School Fleet feels more like a marine school/military hybrid adventure. The show makes it clear that Blue Mermaid is in danger at times especially when combating other ships (the most prominent one being the infamous Musashi). At other times, it feels like a school floating on water. This is because of the inner storytelling that goes inside the ship with the girls living their dream job. They want to have fun while working so on occasions, there will emerge “breather” episodes to show their lifestyle. At other times, they must be prepared for what’s ahead. That is, one particular part of the story baffles me with the way it’s executed when it involves peculiar experimentations. I’m all in for surprises but that took me by storm, almost like the way that Akeno is taken by her unexpected role. For some, this could drive away viewers from further pursuing the series but for others, it may also spark more interest. In retrospect, High School Fleet is one of those shows that you’ll have to expect the unexpected.

It’s an anime original first and produced by TMS Entertainment. For artwork standards, it’s fairly well done in terms of ship designs. This is important because it gives more viewers interest to see how they work. I’m also impressed by the way Harekaze is designed with its 12.7 cm/50 Type 3 naval gun turrets and MK 16 naval guns. The 5"/54 caliber Mark 16 and Mark 37 also looks surprisingly realistic. In terms of character designs, it’s generally moderate with a decent effort and budget poured towards making the girls look adorable and professional. Remember, there are at least 30 girls on just one ship alone! Like most shows that takes almost exclusively at sea, expect fan service with an even inevitable “beach episode”. However, the show itself excels the most at combat choreography. Even the night battles gives a strong impression of what naval warfare about. And in essence, the series knows how to expand its limits to make the fights believable.

The ships are really well animated and they do feel like the girls are on board a real ship with all of its related equipment and weapons. Explosions are also eye candy and pairs well with the sound effects. The ships move realistically, shakes and rides the waves like a ship would. The water animation is of note as well and makes you feel like they are at sea. If you just came for the battles and fights, you’ll be pleased as the weapons are also fairly well animated (torpedoes especially). If you came for the cute girls then you won’t be disappointed either. 31 cuties each with a different style to match their persona and all of them will leave at least some impressionable image in your mind. Although for some reason, it might just be me, but the ships seems to be in a higher resolution than the characters sometimes. However, it’s nothing too significant that can affect the enjoyment of the show.

High School Fleet makes extensive use of CG, which is sure to turn off some people. I don’t think I’m one to immediately dismiss an anime that’s heavy on CG, but I’m unsure how I feel about it here. There are times when it genuinely looks pretty good and you know that a traditional hand-drawn style probably wouldn’t have resulted in the same visual quality, yet there are other times where it just looks so garish and awkward. For me, it wasn’t a deal-breaker or anything, but apart from the CG, this was a decent-looking show that I can’t fault too much. When it comes to the sound, I don’t think HSF is all that exceptional in this regard, but it gets the job done with some reasonably solid music that—while not being overly memorable—doesn’t exactly feel subpar. Overall, I think that the production values are more than sufficient, which is a pretty good word to describe this anime as a whole.

On the subject of soundtrack, the show is crisp and knows what it’s doing most of the time. This is especially true for the intense battle orchestrated OST that really gets the adrenaline pumping. Character voices are also accurately portrayed to reflect their personalities and expressions. Remember, these girls are practically part of the military so it’s interesting to see how they react under extreme circumstances. The voice mannerism does just that. OP and ED theme songs are catchy as well that gives the marine vibes and cool atmospheric feeling.

OP is catchy and gets stuck in your head, ED is soft and calming. Both fits the theme of the sea very well. The sound track during the anime isn’t used to fill the silence but rather used to great effect adding lots of tension to the scenes. Those sound tracks can really get your heart racing during the fight scenes and your heart throbbing in some of the more emotional scenes, and trust me, the feels will hit you like a truck. Other sounds worth mentioning is the sound effects which are pretty good. You can hear the whistle of the shell getting louder as it get nearer to the ship, the heavy explosion during impact, the creaking of the ship under stress, the echo of detonations of torpedoes in the water and the list just goes on. All these sound effect adds more excitement, tension and action to the scenes and boy they feel satisfying.

2018/2/11 posted in  Review

Wipe Out Aliyun Server Guard Agent

Why NOT simply do reinstall via panel?

Server Guard Agent (SGA) is installed by default and Aliyun has an official uninstall guide.

However, after uninstalling SGA, your VM still trying connecting SGA remote and uploading encrypted data.

After blocked all IPs of SGA service, an unknown key inserted in my .ssh/ directory. I opened a ticket, they told me "you were hacked". And I found my sshd binary file was modified.

So we will enable full system encryption to make VMs hosted by a provider which cannot be trusted invulnerable.

Prepare your VM

You’ll install your custom distro onto a raw disk, with the direct disk boot option. The end result will be a working custom install; however, it will not support disk resizing from within the official panel, nor will it be compatible with the official backup service.

1. Create two raw, unformatted disk images. Can be done with Aliyun Console.
2. Create two configuration profiles.

Installer profile

Label: Installer
Kernel: Direct Disk
/dev/sda: Boot disk image.
/dev/sdb: Installer disk image.
root / boot device: Standard /dev/sdb

Boot profile

Label: Boot
Kernel: Direct Disk
/dev/sda: Boot disk image.
root / boot device: Standard /dev/sda

Download and Install Image

  1. Boot into Rescue Mode with your Installer disk mounted to /dev/sda, and connect to your VM using the Aliyun Console.
  2. Once in Rescue Mode, download your installation media and copy it to your Installer disk. In this example we’re using the Ubuntu net installer.
dd if=mini.iso of=/dev/sda
  1. Reboot into your Installer configuration profile
  2. During your installer’s partitioning/installation phase, be sure to instruct it to use the /dev/sda volume and enable full system encryption.
  3. Once the installation completes, reboot into your Boot profile and open the console. You will have access to your VM.
2018/1/11 posted in  Network

Difference between OpenVZ and LXC

Background: What’s a container?

Containers have been around for over 15 years, so why is there an influx of attention for containers? As compute hardware architectures become more elastic, potent, and dense, it becomes possible to run many applications at scale while lowering TCO, eliminating the redundant Kernel and Guest OS code typically used in a hypervisor-based deployment. This is attractive enough but also has benefits such as eliminating performance penalties, increase visibility and decrease difficulty of debug and management.

Because containers share the host kernel, binaries and libraries, can be packed even denser than typical hypervisor environments can pack VM’s.


OpenVZ is a Linux container solution. It was first released in 2005 by SWSoft, now known as Parallels. Though connected to a private, proprietary company, OpenVZ is open source and available for free.

The previously mentioned container projects have been related to BSD. One fundamental difference between BSD and Linux is that Linux is technically just a kernel. All of the tools that make Linux functional are supplemental and from different projects. For example, the chroot command in Ubuntu Linux comes from the GNU coreutils project.

This distinction between BSD and Linux is quite important in the case of OpenVZ. Because containers require kernel level access, the container code needs to be integrated into the kernel. OpenVZ only released its code as a set of patches and custom-compiled Linux kernels they initially never bothered to get their code into the official Linux kernel.

As explained in a recent OpenVZ blog entry, this was a mistake recognized way back in 2005, and the OpenVZ team has been working to get their code integrated into the main Linux kernel since then. This can sometimes be a very slow and painful process. The Xen project went through the same scenario.

OpenVZ has never really gained widespread acceptance in the Linux community. This is unfortunate since it is a very robust project with a large amount of features.


Finally, there is LXC. Well, before we get into LXC, let us talk about Linux Namespaces. A namespace is another term for segregation. Items in different namespaces are unable to collide or conflict with each other. Chroot can be thought of as a simple filesystem namespace.

As we have seen with all the other container projects, they implement features beyond filesystem segregation: users, processes, and the network are all also segregated.

Starting in 2001, the Linux kernel began supporting a series of namespaces. The first was mount namespaces, which can be thought of as an enhanced filesystem namespace. Since then, Linux has added support for UTS, IPC, PID, user, and network namespaces. This article goes into great detail about each of them.

Next, a quick mention about control groups otherwise known as cgroups. Cgroups limit the amount of resources a certain process can use. For example, a process could be limited to use just 50% of the total CPU on the server.

Between namespaces and cgroups, the Linux kernel has everything it needs to support a modern container system. And that is exactly what LXC is a collection of utilities that interact with namespaces and cgroups.

So, since LXC uses features native to the Linux kernel, this should make it a better choice over OpenVZ, right? I guess that depends on one's opinion of those features.

The Linux namespace and cgroup code is still in development. For example, user namespaces were only finalized a few months ago. Shortly after, they were found to be heavily exploitable.

Security in general is a very subjective and relational topic: what one person is paranoid of can be of no matter to another person. Security has always been a hot topic with LXC. Here are several different articles on the subject.

This part of the series summarized various existing container solutions. You might have noticed the added detail for the Linux-based solutions especially LXC.

2017/12/31 posted in  Network

BitTorrent Traffic Detection with Deep Flow Inspection

1. What is Deep Flow Inspection(DFI)?

As the name implies, the analysis or the classification of P2P traffic is a flow-based, focusing on the connection level patterns of P2P applications. Thus, it does not require any payload analysis, unlike DPI. Because it doesn’t require payload analysis, encrypted data packets can be easily supported. The down side of this approach is that there is an additional step of extracting the connection level pattern for the P2P traffics. And yet, there is no rule of thumb for which network feature should be used in this method.

2. Proposed System

2.1 Training Module

スクリーンショット 2017-12-23 12.36.10
** Figure 1: Proposed system to classify BT packet flows **


2.2.1 Ground truth generation

The ground truth is the packet flows with known classes. In order to train a classifier, there are two types of packet flows needed to capture, namely the BT and non-BT packet flows. To capture the BT packets, I manually force the BT client to use a single TCP port (i.e. 1200) for data transfer. Thus, all the BT traffic must go through thisTCP port. Then, I start a sample torrent file and the BT client will automatically start downloading/uploading the contents. At the same time, I start my packet capturing program to obtain the packets.Similarly, to capture non-BT packets, I start my packet capturing program while we were creating non-BT network activities including HTTP,FTP and SSH. With the known class of the packets in the PCAP files, I could start training the classifier.

2.2.2 Study of DFI classifier accuracy

スクリーンショット 2017-12-23 12.38.56
** Figure 2: Classifier accuracy with different training samples **
Figure 2 shows the classifier accuracy with increasing number of BT packet flows used to train the classifier. The classifier was first trained with a set of BT samples, and then it was tested against with some otherBT packet flows to observe the accuracy. This experiment gives us some clues about the number of packet flows should be used in order train a reliable classifier for the DFI module.As expected, the moreBT packets are used to train the classifier, the better the accuracy is. However, as the number of the BT packets increase, the classifier will be saturated at some point. After that, even more packets is provided, the accuracy does not increase significantly.

2.2 Source code:

2017/12/23 posted in  Network