I would like to redirect domain1.com to domain2.com using DNS. I would further like to redirect www.domain1.com to www.domain2.com.  For domain1.com zone file, do I need to have an A record or are CNAME records sufficient, e.g.  *                               IN      CNAME           domain2.com. www.domain1.com                 IN      CNAME           www.domain2.com.   The goal is that when visitors visit domain1.com or www.domain1.com, they go to domain2
Is it possible to set a DNS record to redirect all example.com/* traffic to www.example.com/*?  I'm running a  app on Heroku's .  I set up , and the documentation discusses . I also read about how to do this with . However, I'm wondering if there's a way to do this via DNS, i.e., without hitting my app.
free groups: $F_X\cong F_Y\Rightarrow|X|=|Y|$ I'm reading Grillet's Abstract Algebra. Let $F_X$ denote the free group on the set $X$. I noticed on wiki the claim $$F_X\cong\!\!F_Y\Leftrightarrow|X|=|Y|.$$ How can I prove the right implication (find a bijection $f:X\rightarrow Y$), i.e. that the rank is an invariant of free groups?  I am hoping for a simple and short proof, having all the tools of Grillet at hand. Rotman (Advanced Modern Algebra, p.305) proves it only for $|X|&lt;\infty$, Bogopolski's (Introduction to Group Theory, p.55) proof seems (unnecessarily?) complicated, and Lyndon &amp; Schupp's (Combinatorial Group Theory, p.1) proof I don't yet understand. It's the very first proposition in the book; in the proof, they say:     The subgroup $N$ of $F$ generated by   all squares of elements in $F$ is   normal, and $F/N$ is an elementary   abelian $2$-group of rank $|X|$. (If   $X$ is finite, $|F/N|=2^{|X|}$ finite;   if $|X|$ is infinite, $|F/N|=|X|$). $\square$   Is $N:=\langle w^2;w\in F\rangle$? What is an abelian $2$-group? Elementary? What and how does the above quote really prove? I'm guessing a free abelian group on $X$ is $\langle X|[X,X]\rangle\cong\bigoplus\limits_{x\in X} \mathbb{Z}$?  Can an isomorphism $\varphi:F_X\rightarrow F_Y$ not preserve the length of words? At least one letter words? Computing $\int_{0}^{\pi}\ln\left(1-2a\cos x+a^2\right) \, dx$ What is the function __construct used for? I have been noticing __construct a lot with classes. I did a little reading and surfing the web, but I couldn't find an explanation I could understand. I am just beginning with OOP.  I was wondering if someone could give me a general idea of what it is, and then a simple example of how it is used with PHP? Can I change a user's keyboard input? No CUDA and GPU option I have Blender 2.73a with AMD Radeon 3100 Graphics. I saw  on how to make cycles render faster. It says when I go to User Preferences> System> Compute Device, It has no CUDA option, which means there is no GPU option. How can I fix this? Limit $\frac{x^2y}{x^4+y^2}$ is found using polar coordinates but it is not supposed to exist. I have seen people showing one slide progressively by pressing Enter. Could anyone tell me how to realize that in Beamer? Domain of ProbabilityDistributions I am using postgreSQL, postGIS and pgrouting. Now I am really confused on how am I going to find the shortest path between multiple points.   I know how to find it between two points through dijkstra but I am confused how to accomplish the same result with more than two points.   I have done some research and found this:    But still I did not understand if its the right way and how to install it. I use this command in the terminal to run the minecraft launcher with java 8:  /home/max/Java/jre1.8.0_25/bin/java -jar Minecraft.jar   I included the full java path because I installed it on /home as a normal user and i want to include it.   That command works, it opens the launcher with Java 8 but I want to make a bash file so I don't have to open the terminal. And, most important, I don't want the terminal to remain open when I click play in the Minecraft launcher and the game starts.  Now if i close manually the terminal when the game have started, the game is closed too. I'm using a common charger for both of my laptops.  The charger is specified at 20 Volts and 3.25 Amperes. My other laptop has a specification of 19 V and 3.42 A.  Is it safe to charge my laptop with chargers whose specifications exceed or are not equal to the mentioned specifications?  I have read somewhere that it may cause some damage if the voltage or amperage is not matching the specs. Appendix in LaTeX /var/log/syslog constantly logging errors, growing at 1 MB/s It seems to be the same three errors repeated:  $ tail -n15 /var/log/syslog Apr  5 23:32:01 detoo kernel: [ 6042.078785] ACPI Error: [PGRT] Namespace lookup failure, AE_NOT_FOUND (20150619/psargs-359) Apr  5 23:32:01 detoo kernel: [ 6042.078787] ACPI Error: Method parse/execution failed [\_GPE._L6F] (Node ffff8808554d42d0), AE_NOT_FOUND (20150619/psparse-536) Apr  5 23:32:01 detoo kernel: [ 6042.078788] ACPI Exception: AE_NOT_FOUND, while evaluating GPE method [_L6F] (20150619/evgpe-592)   I noticed something was wrong when I was getting low disk space warnings. I've flashed to the latest UEFI available, I've tried enabling/disabling the C states in my UEFI.  I'm running Linux Mint 17.3 Cinnamon 64-bit with kernel 4.2.0-34-generic. I have a skylake processor and z170 motherboard.  I'm quite new to linux and am at a lost as what I should do next.  EDIT: I have the same problem when booting from a USB with Ubuntu 16.04, and nearly identical error logs being constantly spammed:  Apr  6 01:01:48 ubuntu kernel: [  152.594053] ACPI Exception: AE_NOT_FOUND, while evaluating GPE method [_L6F] (20150930/evgpe-592) Apr  6 01:01:48 ubuntu kernel: [  152.594994] ACPI Error: [PGRT] Namespace lookup failure, AE_NOT_FOUND (20150930/psargs-359) Apr  6 01:01:48 ubuntu kernel: [  152.594996] ACPI Error: Method parse/execution failed [\_GPE._L6F] (Node ffff8808554e02d0), AE_NOT_FOUND (20150930/psparse-542) I use to run  $s =~ s/[^[:print:]]//g;   on Perl to get rid of non printable characters.   In Python there's no POSIX regex classes, and I can't write [:print:] having it mean what I want. I know of no way in Python to detect if a character is printable or not.   What would you do?   EDIT: It has to support Unicode characters as well. The string.printable way will happily strip them out of the output.  curses.ascii.isprint will return false for any unicode character. $P(X<Y)$ where X and Y are exponential with means $2$ and $1$ Git ignore file for Xcode projects Which files should I include in .gitignore when using Git in conjunction with Xcode? Removing all 'stable' theme's CSS from a Drupal 8 custom theme I would like to remove all CSSs automatically included from stable theme:  /core/themes/stable/css/system/components/*   I can remove them one by one inside the .info.yml file:  stylesheets-remove:   - 'core/themes/stable/css/system/components/ajax-progress.module.css'   - 'core/themes/stable/css/system/components/autocomplete-loading.module.css'   - ...   Is there a way to remove all of them at once?   Something like:  stylesheets-remove:   - 'core/themes/stable/css/system/components/*' I want my app automatically know user phone number by accessing their SIM Card Can I use the "Scan" button with SANE? I have an HP Deskjet with integrated scanner. It has a "Scan" button on its top, but this button does not interact with the xsane program on my Debian machine: To get a page scanned, I have to initiate the scanning process from xsane.  Is there a setting (or a scan program) that allows me to press the scan button and cause the program to scan a page? How to align a cluster of points? If you have a cluster of points selected like this:    how do you align the points so that they create a flat plane?