naftuli.wtf An urban mystic, pining for conifers in a jungle of concrete and steel.

The Logitech G700s Mouse

In today’s episode of “discontinued stuff that I rely on,” enter the Logitech G700s mouse. Feast your eyes on this:

Logitech G700s

Before there was the G700s, there was the G700, which was, for all intents and purposes, identical to this mouse but without some of the graphics on the mouse.

Here are a series of images to get you familiar with the layout of the mouse. These are all pictures of the G700 and not the G700s, but the button layout is identical.

An aerial view:

G700 Above

From the side:

G700 Side

Apart from the mouse wheel, its button, and the left and right click buttons, there are eight additional programmable buttons: three near the first finger, one behind the mouse wheel, and four paddles on the side near the thumb.

This is a gaming mouse, but I don’t use it as a gaming mouse; I have programmed it for productivity and hacking.

All the Features

Before we drop into my actual configuration, let’s just run through the features:

  • Uses rechargeable batteries; can simultaneously charge over micro USB and be used. (This wouldn’t be a feature if Apple hadn’t made the Magic Mouse so bad.)
  • Varying DPI settings; anywhere from 200 to 8200(!) DPI is possible.
  • Varying battery use settings; change reports per second to be small to save battery or high for gaming.
  • Scroll wheel with tilt, a middle button, and free/infinity scroll via a toggle: either ratcheting clicks or no resistance/free flowing.
  • Multiple profiles; you can program up to five profiles on the mouse’s firmware and change between them via buttons.

Pretty cool stuff. Let’s discuss how I use it.

Profile 1: Default

My default profile is a pretty well-rounded general productivity setup. I have media control, browser forward/back control, three DPI modes, and an “expose” button to show all windows on my desktop.

Here is the profile configuration:

Default Profile

Additionally, here is a .dat export of the profile that can be imported via the Logitech Gaming Software.

Highlights

From my thumb, I can skip forward and backward in my media player (upper paddles), and can navigate forward and backward in my browser (lower paddles).

From my first finger on top of the mouse, I can cycle through three DPI settings (furthest button), play/pause my media player (middle button), and change the profile (closest button). The button behind the mouse wheel simply executes the “expose” command on my windows for elementary OS.

I have all profiles set to save battery, reporting as seldom as possible.

The DPI settings are:

  • 600: perfect for editing things in Photoshop or GIMP with a high degree of accuracy.
  • 1200: perfect for mousing around on a laptop.
  • 1900: perfect for navigating three 27” 1440p monitors :trollface:

In summary: I can control my media player, the browser, DPI, profile, and manage windows without lifting my hand from my mouse.

Profile 2: BIOS

The other profile I keep around is a BIOS profile for entering and navigating a BIOS menu. This has proved to be quite useful.

Here is the profile configuration:

BIOS Profile

Additionally, here is a .dat export of the profile that can be imported using the Logitech Gaming Software.

Highlights

Left and right click work normally. The middle mouse button will send the Enter key, tilting left on the wheel will send Left, and tilting right on the wheel will send Right. The furthest button on top sends Up, the middle button on top sends Down, and the closest button changes the profile, just like the default profile above. The button behind the mouse wheel sends Delete to trigger the BIOS menu during boot. If your BIOS uses a different key, program that key here.

In summary: I can enter and navigate a BIOS without lifting my hand from my mouse.

Discontinued

Unfortunately, like everything else I love, this mouse and its predecessor have been discontinued by Logitech. I was able to obtain a new one from eBay, but as time goes on, they will likely get harder and harder to obtain.

Logitech hasn’t launched a mouse with a similar form factor since discontinuing it, so until then, HODL.

The Apple USB Keyboard

I can’t quit you babe…

The Apple USB Keyboard

I honestly can’t stop using hardware that isn’t made anymore. Today, I’ll be discussing my favorite keyboard, the Apple Wired USB Keyboard without the num-keys. Let’s break down why I can’t stop using this keyboard.

Media Keys

Simply put, the media keys are right there. I don’t have to look to play/pause or skip tracks, it’s all just a short reach away. Volume up and volume down are right there. Things just work, which is the overarching theme here.

PageUp, PageDown, Home, and End

Probably the most compelling feature of this keyboard on Linux is the key bindings for function keys and arrows:

  • Fn+Up: equivalent to PageUp
  • Fn+Down: equivalent to PageDown
  • Fn+Left: equivalent to Home; moves the cursor to the absolute beginning of the line.
  • Fn+Right: equivalent to End; moves the cursor to the absolute end of the line.

Normally, keyboards throw PageUp, PageDown, Home, and End to a hard-to-reach location in the upper right near the numpad. When this is the case, these keys are very hard to use and so I simply don’t use them.

Placing these as a simple Fn+Direction shortcuts allows me to navigate editors, text editors, browser URL bars… it works everywhere because it’s built into the kernel’s keymap for these keyboards.

Here are some use cases:

  • Need to indent a line more or less? Fn+Left to navigate to the beginning of the line, then Tab, then Fn+Right to head back to the end of the line.
  • Need to delete an entire line? Shift+Fn+Left will select the entire line, and then a simple Backspace or Delete and the line is gone.

The amazing thing about these keys being bound the way that they are is that they mesh very well with normal navigation using Ctrl+Direction; it’s simply a different modifier key to move around the line rather than around words using Ctrl+Direction. It just works, and I have yet to find another keyboard that replicates this extremely important functionality.

I own one of these keyboards for all of my machines, laptops and desktops.

Comfort

It’s hard to gauge comfort, but I don’t get any pain whatsoever using this keyboard. I like the action, and I don’t get fatigue.

It’s hard to discuss whether this will be the same for everybody, I type in Dvorak so I admittedly use the keyboard differently than most people.

USB

It’s USB! Gaming just works. The Apple Wireless Keyboard, being Bluetooth, works around 95% of the time. Sometimes, it’ll disconnect, the batteries die eventually, and with USB all these problems disappear.

On top of this, underneath the keyboard are two USB ports. I typically have my YubiKey hanging off of one and my mouse USB receiver off of the other. The convenience of this cannot be understated.

Epilogue: Find Me a Better Keyboard

I actually ordered a test set from WASD keyboards which demonstrates all of the different types of MX switches. MX Browns are what I would probably use in the end, but that’s contingent on me finding a keyboard which mirrors this layout and has media keys in the same place and supports the same key shortcuts as detailed above.

Find me a mechanical keyboard which does all this, and maybe, just maybe, I’ll be able to move on from these discontinued keyboards I have to obtain via eBay.

Integrating systemctl --user and your Graphical Session

For those of us nerds who have been running Linux on the desktop for years now, the addition of systemd in recent releases has opened up some interesting user service management solutions. While not often discussed, systemctl --user is a per-user systemd service management system which sports most if not all of the features of the parent PID 1 systemd.

One issue I ran into on elementary 0.4 Loki (Ubuntu 16.04) was that the environment of systemctl --user was pretty barren:

naftuli@laststand:~$ systemctl --user show-environment
HOME=/home/naftuli
LANG=en_US.UTF-8
LOGNAME=naftuli
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
SHELL=/bin/bash
USER=naftuli
XDG_RUNTIME_DIR=/run/user/1000

This constitutes the bare minimum of what a user service might need. However, for starting user services on the desktop, this environment doesn’t have a reference back to the DISPLAY or anything else about the desktop session.

I found a workaround for this limitation by defining a script called by the desktop session on login and a user target called user-graphical-login.target which other services can depend on.

My script simply imports the current environment and starts the user-graphical-login.target, allowing other units to start:

#!/usr/bin/env bash

systemctl --user import-environment
systemctl --user start user-graphical-login.target

Drop this wherever you’d like, and then add it as a startup script in your distribution’s startup applications:

Screenshot

Next, let’s define our target at ~/.config/systemd/user/user-graphical-login.target:

[Unit]
Description=User Graphical Login
Requires=default.target
After=default.target

Log out, log back in, and then check that the target has been started:

naftuli@laststand:~$ systemctl --user status user-graphical-login.target
● user-graphical-login.target - User Graphical Login
   Loaded: loaded (/home/naftuli/.config/systemd/user/user-graphical-login.target; static; vendor preset: enabled)
   Active: active since Wed 2017-12-27 11:54:16 PST; 1 day 3h ago

Dec 27 11:54:16 laststand systemd[1938]: Reached target User Graphical Login.
Dec 27 11:54:27 laststand systemd[1938]: Reached target User Graphical Login.

If we now dump the environment from systemd --user, we should now see a ton of environment variables:

DBUS_SESSION_BUS_ADDRESS=unix:abstract=/tmp/dbus-4CdgBoOWOy,guid=54269270bb9eccd9b83e0e1f5a43fa10
DEFAULTS_PATH=/usr/share/gconf/pantheon.default.path
DESKTOP_SESSION=pantheon
DISPLAY=:0
EDITOR=vim
GDMSESSION=pantheon
GDM_LANG=en_US
GIO_LAUNCHED_DESKTOP_FILE=/usr/share/applications/org.pantheon.terminal.desktop
GIO_LAUNCHED_DESKTOP_FILE_PID=3930
GNOME_DESKTOP_SESSION_ID=this-is-deprecated
GPG_TTY=/dev/pts/4
GSETTINGS_SCHEMA_DIR=/home/naftuli/data
GTK_CSD=1
GTK_MODULES=pantheon-filechooser-module:gail:atk-bridge
HOME=/home/naftuli
LANG=en_US.UTF-8
LANGUAGE=en_US
LESSCLOSE=/usr/bin/lesspipe %s %s
LESSOPEN=| /usr/bin/lesspipe %s
LOGNAME=naftuli
LS_COLORS=rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:mi=00:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lrz=01;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.cab=01;31:*.jpg=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.ogv=01;35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.m4a=00;36:*.mid=00;36:*.midi=00;36:*.mka=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.oga=00;36:*.opus=00;36:*.spx=00;36:*.xspf=00;36:
MANDATORY_PATH=/usr/share/gconf/pantheon.mandatory.path
PANTHEON_TERMINAL_ID=0
PATH=/home/naftuli/bin:/home/naftuli/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
POWERLINE_COMMAND=powerline
PROMPT_COMMAND=__bp_precmd_invoke_cmd; dbus-send --type=method_call --session --dest=org.pantheon.terminal /org/pantheon/terminal org.pantheon.terminal.ProcessFinished string:$PANTHEON_TERMINAL_ID string:"$(history 1 | cut -c 8-)" >/dev/null 2>&1;  __bp_interactive_mode;
PWD=/home/naftuli
QT_ACCESSIBILITY=1
QT_IM_MODULE=ibus
QT_LINUX_ACCESSIBILITY_ALWAYS_ON=1
QT_STYLE_OVERRIDE=gtk
SESSION_MANAGER=local/laststand:@/tmp/.ICE-unix/2023,unix/laststand:/tmp/.ICE-unix/2023
SHELL=/bin/bash
SHLVL=2
SSH_AGENT_PID=2095
SSH_AUTH_SOCK=/home/naftuli/.gnupg/S.gpg-agent.ssh
TERM=screen-256color
TMUX=/tmp/tmux-1000/default,1956,1
TMUX_PANE=%1
USER=naftuli
VTE_VERSION=4205
XAUTHORITY=/home/naftuli/.Xauthority
XDG_CONFIG_DIRS=/etc/xdg/xdg-pantheon:/etc/xdg
XDG_CURRENT_DESKTOP=Pantheon
XDG_DATA_DIRS=/usr/share/pantheon:/usr/local/share/:/usr/share/
XDG_GREETER_DATA_DIR=/var/lib/lightdm-data/naftuli
XDG_MENU_PREFIX=gnome-
XDG_RUNTIME_DIR=/run/user/1000
XDG_SEAT=seat0
XDG_SEAT_PATH=/org/freedesktop/DisplayManager/Seat0
XDG_SESSION_DESKTOP=pantheon
XDG_SESSION_ID=c2
XDG_SESSION_PATH=/org/freedesktop/DisplayManager/Session0
XDG_SESSION_TYPE=x11
XDG_VTNR=7
XMODIFIERS=@im=ibus
_=/bin/systemctl

Now, your user services can start graphical applications and interact with the session.

2017Q4HW: Desktop Monitor Roundup

It’s Q4 of 2017 and I’m in the market for new hardware. I’ve been wanting new monitors for my desktop for some time now, so I thought I’d provide my process and my findings for what’s important for modern desktop monitors.

Displays are something that will likely outlast multiple PC builds, so it’s important to choose displays that will last as long as possible, taking into account features you’d like to retain for the next 5-10 years. We’ll now discuss the various facets of choosing the right monitor.

Physical Size vs. Resolution

This is arguably the easiest part of selecting a monitor for me. 27” monitors have been around for a long time and for me they’re the de facto standard. As for resolution, 2560x1440 is a dream at this display size. Text is crisp, and on-screen real-estate is plentiful.

On a single monitor, it’s realistic to put two windows side-by-side which is helpful when simultaneously reading documentation and writing code. With my setup at work with three, 27”, 2560x1440 Dell U2717D monitors laid out horizontally, I can have my music player, Slack, Signal Desktop, two Atom text editor windows, and a browser: each of these vertically maximized and horizontally divided on each display.

Work Setup

The U2717D is currently on Amazon for around $440. Since I’m needing three of these, every dollar counts.

Bezel

Another win for the U2717D: bezel size. If you’re laying out multiple monitors next to each other, a wide bezel breaks up the display, leaving unavoidable gaps between the monitors.

Compare the U2717D:

U2717D

…with my previous monitors, ancient ViewSonic VX2739WMs:

Remember that whatever your bezel is, it is doubled when you put two monitors next to each other. This makes for a two inch gap at home with the ViewSonics versus maybe a half an inch at work with the Dells.

If you’re not planning on a multiple monitor setup, disregard the bezel, unless you like the almost edgeless aesthetic.

Density, AKA DPI

Density is where the Dells fall short. A 4K display at the same physical screen size of 27” has 1,280 more pixels horizontally and 720 more pixels vertically. Due to double the pixels vertically and double the pixels horizontally, a 4K display achieves 1080p at double the density. Text is extremely sharp and HiDPI images look amazing.

The reason I’m not interested in 4K for my setup is just that: 4K is 1080p at double the density. On the other hand, a 5K display is 1440p at double the density. At work, some engineers have 5K displays at 27” and they are absolutely gorgeous.

LG UltraFine 5K

The downside? There are a few:

  • $1,300 price tag. You can have three Dell U2717D displays for the price of one of these 5K displays.
  • Power draw: drawing 14.7 million pixels ain’t cheap. With EPA power saving on, your draw is going to be 140W for each of these.
  • GPU power. With the latest NVIDIA GTX 1080 Ti, you can drive at most two of these displays. It might be possible to use SLI, but prepare to hear your fans all the time forever.

It may be possible that in the future, using technologies like NVIDIA’s GSync, power draw and GPU demand will be driven down to the bare minimum required to display something at any one given time. More specifically, it could be possible to lower the refresh rate to 1Hz when the displays are idle, tremendously reducing the GPU and power requirements for an average desktop setup.

My conclusion: 5K is what you want, but for multiple displays, it’s still way out of reach unless money and power are no object.

Display Technology

One thing that’s often neglected in these discussions is the underlying display technology. The main two contenders in this field are IPS and OLED, with heavy bias in desktop and laptop displays toward IPS: almost every display you’ll find is IPS unless you go out of your way.

If the market is so biased, why should one care?

Open this web-page and maximize it so that your entire display is black. On an IPS display (most likely like the one you’re reading this on right now), you’ll clearly see the edges of your display against your bezel. This is because IPS displays have a backlight. Pixels that are entirely black are still backlit, leaving you with a noticeable glow on your display.

On the other hand, OLED displays do not have a backlight. Your phone may have an OLED display. If you open the same web page on an OLED display, you will not see any glow whatsoever. A fully black pixel is one that is completely and totally off.

Some new laptops like the Dell XPS 13 and the ThinkPad X1 Yoga have OLED displays, but they’re still relatively rare. I’m able to find OLED TVs, but not one single desktop monitor. Fingers crossed for 2018, folks.

Refresh Rate

This primarily concerns the gamers out there and not so much those of us who primarily use our computers for work, but refresh rates are a feature you’re likely to think about regardless. Almost every monitor these days have a refresh rate of 60Hz, or 60 times/frames per second.

At 60FPS, it’s still likely that you’ll notice motion blur and screen tearing at times. Recently, new monitors have entered the market which support 120Hz, 144Hz, or even 165Hz refresh rates.

ASUS PG279Q

Above is the ASUS PG279Q 27” monitor, with a 1440p resolution and up to 165Hz refresh rate using NVIDIA’s GSync technology.

Now, the downside of refreshing 165 times per second is that GPUs will have to work that much harder to redraw the display. Your GPU can redraw two 1440p monitors at 60Hz with less GPU load than one of these high refresh rate monitors.

This isn’t fully true, as NVIDIA’s GSync and AMD’s FreeSync allow the monitor and the GPU to speak directly to one another, slowing down the refresh rate when low or no activity is occuring on-screen. This is a huge boon for GPU load in multi-monitor setups: if you’re gaming on your center display and not on your left and right displays, those monitors will reduce their refresh rate and only the center display will be driving a heavy load on the GPU.

The ASUS PG279Q is around $750 right now, so it’s around $150 more per display as opposed to the Dell U2717D.

Bottom line: if you’re going to get a high refresh rate monitor, make sure to find a monitor with GSync or FreeSync ( as is appropriate for your GPU) to optimize the load on your GPU and to save power both on the GPU and on the monitor.

Color

One of the more subtle parts of selecting a monitor is the color profile. If at all possible, don’t mix different monitors in a single setup. Even for me, two different factory runs of the ViewSonics led to dramatically different color response on each display. Dell has a good history of getting color right. Otherwise, your mileage may vary.

If you’re super anal and OCD, buying a USB color calibrator can help you tune your monitors to nearly identical output. With the Dells I have at work, I can’t discern any difference between the monitors, so consider this a side quest.

Power Draw

At standby, the Dell U2717D consumes 0.5W of power, on average it consumes 36W, and at maximium load it consumes 88W of power. If you’re running multiple monitors, wattage adds up and you might see it on your energy bill.

The ASUS PG279Q 165Hz monitor consumes 0.5W at idle and up to 90W under load.

Notably, the LG UltraFine 5K display consumes up to 140W of power, which isn’t surprising given how many pixels it needs to draw.

Physical Characteristics

Finally, you’ll want to optimize for weight and depth. Monitors lighter in weight are generally preferable, but as is often the case, beggars can’t be choosers.

Stands

Triple monitor stands used to be hard to come by, but are now becoming much more generally available.

Here is the KONTOUR Triple Monitor Mount, retailing at around $250:

It supports 27” monitors, which isn’t too common for triple monitor mounts.

Conclusion

To reiterate: monitors last a long time, so choose wisely. What you buy today may very well still be on your desk in ten years. Hopefully this article has clarified the various criteria by which you should choose your next monitor.

Blue/Green Deployments with Route 53

Blue-green deployments with Route 53 involve transferring traffic from one endpoint to another using weighted DNS records. We can automate this relatively easily via the AWS CLI and jq, though there are a few things that are left to be desired: the syntax is quite verbose for updating DNS records.

Finding Your Hosted Zone

We can find a hosted zone id by its name using the following AWS CLI script, tranformed with jq:

$ aws route53 list-hosted-zones | jq -r --arg name domain.com. \
     '.HostedZones[] | select(.Name == $name and .Config.PrivateZone == false) | .Id | ltrimstr("/hostedzone/")'
147MAIJCWVL9PC

Do note that the trailing . is important due to our jq matching. Now that we have our hosted zone, we can use it to discover our records.

Discovering Record Identifiers

Weighted record sets have identifiers so that they can be uniquely referenced and updated. Let’s discover those records and their identifiers.

$ aws route53 list-resource-record-sets --hosted-zone-id 147MAIJCWVL9PC \
    --query "ResourceRecordSets[?Name=='www.domain.com.']" | jq .
[
  {
    "Name": "www.domain.com.",
    "Type": "CNAME",
    "Weight": 100,
    "TTL": 1,
    "SetIdentifier": "blue",
    "ResourceRecords": [
      { "Value": "blue.domain.com" }
    ]
  },
  {
    "Name": "www.domain.com.",
    "Type": "CNAME",
    "Weight": 0,
    "TTL": 1,
    "SetIdentifier": "green",
    "ResourceRecords": [
      { "Value": "green.domain.com" }
    ],
  }
]

We have now obtained our record sets with their identifiers. Unfortunately, due to the nature of what the AWS API and CLI expect, we’ll need these full literal values to make updates.

Shifting Traffic

Now that we have obtained our two record set identifers and their weights, we can begin to transfer traffic. It is unfortunately necessary to send all DNS record related data in the request, so it is not possible to omit things:

$ aws route53 change-resource-record-sets --hosted-zone-id 147MAIJCWVL9PC --change-batch '
{
  "Comment": "{ blue: 90, green: 10 }",
  "Changes": [
    {
      "Action": "UPSERT",
      "ResourceRecordSet": {
        "Name": "www.domain.com.",
        "Type": "CNAME",
        "TTL": 60,
        "Weight": 90,
        "SetIdentifier": "blue",
        "ResourceRecords": [{ "Value": "blue.domain.com" }]
      }
    },
    {
      "Action": "UPSERT",
      "ResourceRecordSet": {
        "Name": "www.domain.com.",
        "Type": "CNAME",
        "TTL": 60,
        "Weight": 10
        "SetIdentifier": "green",
        "ResourceRecords": [{ "Value": "green.domain.com" }]
      }
    }
  ]
}'

In this change set that we have requested, we have shifted to 90% traffic to blue, 10% traffic to green. The output from this command is:

{
  "ChangeInfo": {
    "Id": "/change/C1F72YWO0VLCD8",
    "Status": "PENDING",
    "Comment": "{ blue: 90, green: 10 }",
    "SubmittedAt": "2017-02-01T22:35:52.221Z"
  }
}

We can use this value to then wait for the change to fully propagate:

$ aws route53 wait resource-record-sets-changed --id "/change/C1F72YWO0VLCD8"

Once this has completed, the update will have been propagated to all Amazon nameservers. This process can be looped in order to complete the deployment, shifting traffic in batches until completed.

It is important in addition to waiting for nameserver synchronization that DNS TTLs be observed; if your TTL is 60 seconds, you must wait at least a minute after synchronization has been achieved across nameservers so that clients will respect the changes to DNS, if the clients behave :wink:, which with DNS isn’t always guaranteed.