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This article mainly shows you "how to quickly detect whether a website is down at the Linux terminal". The content is easy to understand and clear. I hope it can help you solve your doubts. Let me lead you to study and learn this article "how to quickly detect whether a website is down at a Linux terminal".

Method 1: use the fping command to detect whether a website is down

The fping command is a ping-like program that uses the Internet Control message Protocol (ICMP) echo request message echo request to determine whether the target host can respond. Fping differs from ping in that it can ping any number of hosts in parallel or read host names from a text file. After fping sends an ICMP echo request, it sends the request to the next target host in polling mode without waiting for a response from the target host. If a target host responds, it is marked as alive and then removed from the check target list. If a target host does not respond within a limited time and / or number of retries, it is designated as unreachable for the site.

# fping 2daygeek.com linuxtechnews.com magesh.co.in 2daygeek.com is alivelinuxtechnews.com is alivemagesh.co.in is alive method 2: use the http command to detect whether a website is down

HTTPie (pronounced aitch-tee-tee-pie) is a command line HTTP client. Httpie is a modern tool that can interact with web services through CLI. The httpie tool provides simple http commands that can produce colorful output by sending simple, natural language syntax HTTP requests. HTTPie can be used for testing, debugging, and basic interaction with HTTP servers.

# http 2daygeek.com HTTP/1.1 301Moved PermanentlyCF-RAY: 535b66722ab6e5fc-LHRCache-Control: max-age=3600Connection: keep-aliveDate: Thu, 14 Nov 2019 19:30:28 GMTExpires: Thu, 14 Nov 2019 20:30:28 GMTLocation: https://2daygeek.com/Server: cloudflareTransfer-Encoding: chunkedVary: Accept-Encoding method 3: use the curl command to detect whether a website is down

The curl command is a tool for transferring data between servers through supported protocols (DICT, FILE, FTP, FTPS, GOPHER, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMTP, SMTPS, TELNET, and TFTP). This tool does not support user interaction. Curl also supports the use of proxies, user authentication, FTP uploads, HTTP POST requests, SSL connections, cookie, breakpoint resumes, Metalink, and so on. Curl is provided with all transport-related capabilities by the libcurl library.

# curl-I https://www.magesh.co.in HTTP/2 200date: Thu, 14 Nov 2019 19:39:47 GMTcontent-type: text/htmlset-cookie: _ _ cfduid=db16c3aee6a75c46a504c15131ead3e7f1573760386; expires=Fri, 13-Nov-20 19:39:46 GMT; path=/; domain=.magesh.co.in HttpOnlyvary: Accept-Encodinglast-modified: Sun, 14 Jun 2015 11:52:38 GMTx-cache: HIT from Backendcf-cache-status: DYNAMICexpect-ct: max-age=604800, report-uri= "https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"server: cloudflarecf-ray: 535b74123ca4dbf3-LHR

If you only want to see the HTTP status code instead of all the information returned, use the following curl command:

# curl-I "www.magesh.co.in" 2 > & 1 | awk'/ HTTP\ / / {print $2} '200

If you want to see if a website is down, use the following bash script:

# vi curl-url-check.sh #! / bin/bashif curl- I "https://www.magesh.co.in" 2 > & 1 | grep-w" 200\ | 301 "; then echo" magesh.co.in is up "else echo" magesh.co.in is down "fi

When you add the contents of the script to a file, execute the file and view the results:

# sh curl-url-check.sh HTTP/2 200magesh.co.in is up

If you want to see the status of multiple sites, use the following shell script:

# vi curl-url-check-1.sh #! / bin/bashfor site in www.google.com google.co.in www.xyzzz.comdoif curl- I "$site" 2 > & 1 | grep-w "200\ | 301"; then echo "$site is up" else echo "$site is down" fiecho "- -" done "

When you add the contents of the above script to a file, execute the file and view the results:

# sh curl-url-check-1.sh HTTP/1.1 200 OKwww.google.com is up--HTTP/1.1 301 Moved Permanentlygoogle.co.in is up--www.xyzzz.com is down- Method 4: use the wget command to detect whether a website is down

The wget command (formerly Geturl) is a free and open source command-line download tool that fetches files through HTTP, HTTPS, FTP, and other widely used Internet protocols. Wget is a non-interactive command-line tool named after World Wide Web and get. Wget is better than other tools, including background running, recursive downloading, multi-file downloading, breakpoint continuation, non-interactive downloading and large file downloads.

# wget-S-- spider https://www.magesh.co.in Spider mode enabled. Check if remote file exists.--2019-11-15 01 CA certificate 2200 https://www.magesh.co.in/Loaded CA certificate'/ etc/ssl/certs/ca-certificates.crt'Resolving www.magesh.co.in (www.magesh.co.in) … 104.18.35.52,104.18.34.52,2606, 4700, 30, 6812, 2334, … Connecting to www.magesh.co.in (www.magesh.co.in) | 104.18.35.52 |: 443... Connected.HTTP request sent, awaiting response... HTTP/1.1 200 OK Date: Thu, 14 Nov 2019 19:52:01 GMT Content-Type: text/html Connection: keep-alive Set-Cookie: _ _ cfduid=db73306a2f1c72c1318ad4709ef49a3a01573761121; expires=Fri, 13-Nov-20 19:52:01 GMT; path=/; domain=.magesh.co.in HttpOnly Vary: Accept-Encoding Last-Modified: Sun, 14 Jun 2015 11:52:38 GMT X-Cache: HIT from Backend CF-Cache-Status: DYNAMIC Expect-CT: max-age=604800, report-uri= "https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct" Server: cloudflare CF-RAY: 535b85fe381ee684-LHRLength: unspecified [text/html] Remote file exists and could contain further links,but recursion is disabled-- not retrieving.

If you only want to see the HTTP status code instead of all the returned results, use the following wget command:

# wget-- spider-S "www.magesh.co.in" 2 > & 1 | awk'/ HTTP\ / / {print $2} '200

If you want to see if a website is down, use the following bash script:

# vi wget-url-check.sh #! / bin/bashif wget--spider-S "https://www.google.com" 2 > & 1 | grep-w" 200\ | 301 "; then echo" Google.com is up "else echo" Google.com is down "fi

When you add the contents of the script to a file, execute the file and view the results:

# wget-url-check.sh HTTP/1.1 200 OKGoogle.com is up

If you want to see the status of multiple sites, use the following shell script:

# vi curl-url-check-1.sh #! / bin/bashfor site in www.google.com google.co.in www.xyzzz.comdoif wget-- spider-S "$site" 2 > & 1 | grep-w "200\ | 301"; then echo "$site is up" else echo "$site is down" fiecho "- -" done

When you add the contents of the above script to a file, execute the file and view the results:

# sh wget-url-check-1.sh HTTP/1.1 200 OKwww.google.com is up--HTTP/1.1 301 Moved Permanentlygoogle.co.in is up--www.xyzzz.com is down- Method 5: use the lynx command to detect whether a website is down

Lynx is a highly configurable text-based web browser used on the addressable cursor character unit terminal cursor-addressable character cell terminals. It is the oldest web browser and is still under active development.

# lynx-head-dump http://www.magesh.co.in HTTP/1.1 200 OKDate: Fri, 15 Nov 2019 08:14:23 GMTContent-Type: text/htmlConnection: closeSet-Cookie: _ cfduid=df3cb624024b81df7362f42ede71300951573805662; expires=Sat, 14-Nov-20 08:14:22 GMT; path=/; domain=.magesh.co.in; HttpOnlyVary: Accept-EncodingLast-Modified: Sun, 14 Jun 11:52:38 GMTX-Cache: HIT from BackendCF-Cache-Status: DYNAMICServer: cloudflareCF-RAY: 535fc5704a43e694-LHR

If you only want to see the HTTP status code instead of all the returned results, use the following lynx command:

# lynx-head-dump https://www.magesh.co.in 2 > & 1 | awk'/ HTTP\ / / {print $2} '200

If you want to see if a website is down, use the following bash script:

# vi lynx-url-check.sh #! / bin/bashif lynx- head-dump http://www.magesh.co.in 2 > & 1 | grep-w "200\ | 301"; then echo "magesh.co.in is up" else echo "magesh.co.in is down" fi

When you add the contents of the script to a file, execute the file and view the results:

# sh lynx-url-check.sh HTTP/1.1 200 OKmagesh.co.in is up

If you want to see the status of multiple sites, use the following shell script:

# vi lynx-url-check-1.sh #! / bin/bashfor site in http://www.google.com https://google.co.in http://www.xyzzz.comdoif lynx- head-dump "$site" 2 > & 1 | grep-w "200\ | 301"; then echo "$site is up" else echo "$site is down" fiecho "- -" done "

When you add the contents of the above script to a file, execute the file and view the results:

# sh lynx-url-check-1.sh HTTP/1.0 200 OK http://www.google.com is up--HTTP/1.0 301 Moved Permanently https://google.co.in is up--www.xyzzz.com is Down-- method 6: use the ping command to detect whether a website is down

The ping command (Packet Internet Groper) is a representative of the network tool used to test the availability / connectivity of a target host in an Internet Protocol (IP) network. The availability of the host is tested by sending an ICMP echo request packet to the target host and waiting for the ICMP echo response message. It calculates the result data based on sent packets, received packets, and lost packets, usually including minimum / average / maximum response time.

# ping-c 5 2daygeek.com PING 2daygeek.com (104.27.157.177) 56 (84) bytes of data.64 bytes from 104.27.157.177 (104.27.157.177): icmp_seq=1 ttl=58 time=228 ms64 bytes from 104.27.157.177 (104.27.157.177): icmp_seq=2 ttl=58 time=227 ms64 bytes from 104.27.157.177 (104.27.157.177): icmp_seq=3 ttl=58 time=250 ms64 bytes from 104.27.157.177 (104.27.157) .177): icmp_seq=4 ttl=58 time=171 ms64 bytes from 104.27.157.177 (104.27.157.177): icmp_seq=5 ttl=58 time=193 ms-2daygeek.com ping statistics-5 packets transmitted 5 received, 0% packet loss, time 13244msrtt min/avg/max/mdev = 170.668 ms 213.824max 250.295 ms add 1: use the telnet command to detect whether a website is down

The telnet command is an ancient network protocol that uses the TELNET protocol to communicate with multiple hosts in a TCP/IP network. It connects to other devices such as computers and network devices through port 23. Telnet is an insecure protocol, and it is not recommended because the data sent by this protocol is not encrypted and may be intercepted by hackers. Everyone uses the encrypted and very secure SSH protocol instead of telnet.

# telnet google.com 80 Trying 216.58.194.46... Connected to google.com.Escape character is'^]. ^] telnet > quitConnection closed. Add 2: use bash scripts to detect whether a website is down

In short, a shell script is a file that contains a series of commands. Shell reads from the file are executed line by line in input order on the command line. To make it more effective, let's add some conditions. This also reduces the burden on Linux administrators.

If you want to use the wget command to see the status of multiple sites, use the following shell script:

# vi wget-url-check-2.sh #! / bin/bashfor site in www.google.com google.co.in www.xyzzz.comdoif wget--spider-S "$site" 2 > & 1 | grep-w "200\ | 301" > / dev/null; then echo "$site is up" else echo "$site is down" fidone

When you add the contents of the above script to a file, execute the file and view the results:

# sh wget-url-check-2.sh www.google.com is upgoogle.co.in is upwww.xyzzz.com is down

If you want to use the wget command to see the status of multiple sites, use the following shell script:

# vi curl-url-check-2.sh #! / bin/bashfor site in www.google.com google.co.in www.xyzzz.comdoif curl- I "$site" 2 > & 1 | grep-w "200\ | 301" > / dev/null; then echo "$site is up" else echo "$site is down" fidone

When you add the contents of the above script to a file, execute the file and view the results:

# sh curl-url-check-2.sh www.google.com is upgoogle.co.in is upwww.xyzzz.com is down above are all the contents of the article "how to quickly detect whether a website is down at a Linux terminal". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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