nfs – Google Cloud Filestore, How to limit the disk usage of each user directory?

I’m currently using Google Cloud Filestore to store user data. Each user has a separate directory, in which they can store any data they want.

However, as the users grow, the capacity cannot handle all the uploaded files. Therefore, I want to set the usage limit of each directory (for example, /my_filestore/alex can only store up to 10GB).

At first, I plan to use quota utility tool, but this tool cannot work with NFS mounting, as NFS.mount does not allow usrquota option.

Is there any other alternative to do implement this restriction? Thanks so much.

air travel – How can I control Internet usage when using in-flight wifi?

Android – Block Automatic Updates & Firewall

Block Automatic Updates

If you are only concerned about “System Updates”, you may want to disable the automatic updates on your device, prior to your flight.

  • Go to Settings > Apps.
  • Navigate to Manage Apps > All Apps.
  • Find an app called Software Update, System Updates or anything similar, since different device manufacturers have named it different.
  • To disable system update, try any of these two methods, the first one being recommended:
    Tap Turn Off or Disable button and then OK. In case this button is grayed out, tap on Force Stop > OK to turn the process off temporarily. In such case, there is a possibility that the app may turn on automatically after some time. The app will surely be turned on again after the system reboot or if you check for updates manually.

Prevent Update

Firewall

If you are only concerned about apps auto updating, you could setup a firewall and configure which apps can access what. A popular Android Firewall app for this is AFWall.

AFWall+ (Android Firewall +) is a front-end application for the powerful iptables Linux firewall.It allows you to restrict which applications are permitted to access your data networks (2G/3G and/or Wi-Fi and while in roaming). Also you can control traffic within LAN or while connected through VPN.

And from their open source repository on GitHub:

Android Firewall+ (AFWall+) is an advanced iptables editor (GUI) for Android. It provides fine-grained control over which Android apps are allowed to access the network.

iOS 12 – Disable Software Updates & Background App Refresh

Disable Software Update

  • On your iPhone, launch Settings and select General > Software Update.
  • Select Automatic Updates. Note, if your iPhone currently has pending updates they will be displayed here.
  • Toggle Automatic Updates off (left/white).

iOS photo for disable system updates

Background App Refresh

To restrict iOS apps from refreshing content when on Wi-Fi (or cellular) you can turn them off in “Background App Refresh” settings of your device.

  • Go to Settings.
  • Click on General.
  • Scroll to bottom and choose: Background App Refresh
  • Switch off the App you want to remove from refreshing OR Switch it off entirely for all apps at the top menu.

Background App Refresh

Background App Refresh allows apps to refresh their content when on Wi-Fi or cellular in the background.

macOS – Disable Automatic Updates (App and System)

Disable Automatic App Updates

According to this MacObserver article for macOS 14.1 Mojave, you should…

  • Start by clicking on the Apple Menu in the upper-left corner of your screen and choosing “App Store.”
  • Choose App Store > Preferences.
  • Deselect the “Automatic Updates” checkbox

Disable Automatic macOS System Updates

  • Open the Apple Menu and choose “System Preferences”
  • Click on “Software Update.”
  • Deselect the “Automatically keep my Mac up to date” checkbox at the bottom.
  • Or if you’d prefer, you can click on the “Advanced” button to individually select what items you’d like to have automatically update—and which ones you don’t want to give that power to.

According to Apple support article, if you’re using OS X El Capitan v10.11.5 or later, you should turn off background downloads. I am not sure what OS X you are using, since you did not specify.

c++ – Append function in and it’s usage

I have some trouble with TArray function in UE4 and got two <Tarray> functions should be Append-ed and woundering what is the correct way to append those two TArrays.

void AGrid::CreateLine(FVector Start, FVector End, float Thickness,const TArray<FVector> &Vertices, TArray<int32> &Triangles)
{
    float HalfThichness = Thickness / 2;
    FVector ThichnessDirection = UKismetMathLibrary::Cross_VectorVector(UKismetMathLibrary::Normal(End - Start, 0.0001), { 0.0f, 0.0f, 1.0f });
    //First TArray with &Triangles as append
    TArray<int32> tArray;
    tArray.Add(Vertices.Num() + 2);
    tArray.Add(Vertices.Num() + 1);
    tArray.Add(Vertices.Num() + 0);
    tArray.Add(Vertices.Num() + 2);
    tArray.Add(Vertices.Num() + 3);
    tArray.Add(Vertices.Num() + 1);
    Triangles.Append(tArray);
//Secound Append function with vArray as the append with &Vertices.
    TArray<FVector> vArray;
    vArray.Add(Start + (ThichnessDirection * HalfThichness));
    vArray.Add(End + (ThichnessDirection * HalfThichness));
    vArray.Add(Start - (ThichnessDirection * HalfThichness));
    vArray.Add(End - (ThichnessDirection * HalfThichness));
    vArray.Append(Vertices); //tried Veritices.Append(), but showed error code E1087
}

So the question is: what is the correct way to append those two TArrays?

public key infrastructure – What are requirements of Key Usage extension of parent and child certificates?

https://tools.ietf.org/html/rfc5280.html#section-4.2.1.3 has this to say:

If the keyUsage extension is present, then the subject public key
MUST NOT be used to verify signatures on certificates or CRLs unless
the corresponding keyCertSign or cRLSign bit is set. If the subject
public key is only to be used for verifying signatures on
certificates and/or CRLs, then the digitalSignature and
nonRepudiation bits SHOULD NOT be set. However, the digitalSignature
and/or nonRepudiation bits MAY be set in addition to the keyCertSign
and/or cRLSign bits if the subject public key is to be used to verify
signatures on certificates and/or CRLs as well as other objects.

So the expectation is that a CA’s KeyUsage will assert { keyCertSign | cRLSign } without asserting digitalSignature. And the end-entity/leaf cert will of course want to assert digitalSignature, therefore there’s no expectation of subsetting.