{"id":6016,"date":"2026-06-19T09:04:00","date_gmt":"2026-06-19T00:04:00","guid":{"rendered":"https:\/\/www.freelifemakers.org\/wordpress\/?p=6016"},"modified":"2026-06-19T09:04:07","modified_gmt":"2026-06-19T00:04:07","slug":"linux-xubuntu-install-openssh","status":"publish","type":"post","link":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/2026\/06\/19\/linux-xubuntu-install-openssh\/","title":{"rendered":"[Linux,Xubuntu]OpenSSH \uc124\uce58 \ubc0f \uc0ac\uc6a9 \/ Installing and Using OpenSSH"},"content":{"rendered":"\n<p>\ud83d\udc49\ud83c\udffb open ssh\ub294 \ub124\ud2b8\uc6cc\ud06c\ub97c \ud1b5\ud574 \ucef4\ud4e8\ud130\uc5d0 \uc548\uc804\ud558\uac8c \uc6d0\uaca9 \uc811\uc18d\ud560 \uc218 \uc788\ub3c4\ub85d \ud574\uc8fc\ub294 \uc624\ud508\uc18c\uc2a4 \ubcf4\uc548 \ud504\ub85c\uadf8\ub7a8\uc785\ub2c8\ub2e4.<br>OpenSSH is an open-source security program that enables secure remote access to computers over a network.<\/p>\n\n\n\n<p>\ud83d\udc49\ud83c\udffb \uc608\uc804\uc5d0\ub294 telnet\uc774\ub098 ftp\ub97c \uc0ac\uc6a9\ud588\uc5c8\ub294\ub370 \ub124\ud2b8\uc6cc\ud06c \uc0c1\uc5d0\uc11c \ubaa8\ub4e0 \uc815\ubcf4\uac00 \ud3c9\ubb38\uc73c\ub85c \uc804\ub2ec \ub418\uae30\ub54c\ubb38\uc5d0 \ud574\ud0b9\uc758 \uc704\ud5d8\uc774 \uc788\uc2b5\ub2c8\ub2e4.<br>In the past, Telnet or FTP was used, but these carry a risk of hacking because all information is transmitted over the network in plaintext.<\/p>\n\n\n\n<p>\ud83d\udc49\ud83c\udffb \uadf8\ub798\uc11c \ub124\ud2b8\uc6cc\ud06c\ub85c \uc811\uc18d\uc2dc \ubaa8\ub4e0 \uc5f0\uacb0\uc744 \uc554\ud638\ud654\ud574\uc11c \ud574\ud0b9\uc744 \ubc29\uc9c0\ud569\ub2c8\ub2e4.<br>Therefore, all connections are encrypted when accessing the network to prevent hacking.<\/p>\n\n\n\n<p>\ud83d\udc49\ud83c\udffb \uc8fc\uc694\uae30\ub2a5 \/ Key Features<\/p>\n\n\n\n<p>\u2714\ufe0f \uc554\ud638\ud654 \ud1b5\uc2e0: \uc811\uc18d\ud558\ub294 \ubaa8\ub4e0 \ub370\uc774\ud130(\ube44\ubc00\ubc88\ud638, \uba85\ub839\uc5b4 \ub4f1)\ub97c \uc554\ud638\ud654\ud558\uc5ec \ud574\ud0b9\uc744 \ubc29\uc9c0\ud569\ub2c8\ub2e4.<br>Encrypted Communication: Encrypts all transmitted data (passwords, commands, etc.) to prevent hacking.<\/p>\n\n\n\n<p>\u2714\ufe0f \uc6d0\uaca9 \uc81c\uc5b4: \ud14d\uc2a4\ud2b8 \uba85\ub839\ucc3d(CLI)\uc744 \ud1b5\ud574 \uba40\ub9ac \uc788\ub294 \uc11c\ubc84\ub97c \ub0b4 \ucef4\ud4e8\ud130\ucc98\ub7fc \uc870\uc791\ud569\ub2c8\ub2e4.<br>Remote Control: Operate a remote server as if it were your own computer via a text command interface (CLI).<\/p>\n\n\n\n<p>\u2714\ufe0f \uc548\uc804\ud55c \ud30c\uc77c \uc804\uc1a1: SCP\ub098 SFTP \uae30\ub2a5\uc744 \ud3ec\ud568\ud558\uace0 \uc788\uc5b4 \ud30c\uc77c\uc744 \uc548\uc804\ud558\uac8c \uc8fc\uace0\ubc1b\uc744 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<br>Secure File Transfer: It includes SCP and SFTP capabilities, allowing for the secure exchange of files.<\/p>\n\n\n\n<p>\u2714\ufe0f \ud3ec\ud2b8 \ud3ec\uc6cc\ub529: \ub85c\uceec\uacfc \uc6d0\uaca9 \ucef4\ud4e8\ud130\uc758 \ub124\ud2b8\uc6cc\ud06c \ud1b5\ub85c\ub97c \uc548\uc804\ud558\uac8c \uc5f0\uacb0\ud574 \uc90d\ub2c8\ub2e4.<br>Port Forwarding: Securely establishes a network connection between local and remote computers.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\ud83d\udc49\ud83c\udffb1.\u00a0<strong>OpenSSH(Open Secure Shell))<\/strong><br>Installing OpenSSH(Open Secure Shell)) <\/h2>\n\n\n\n<p>\u2714\ufe0f\uae30\ubcf8\uc801\uc73c\ub85c Xubuntu\ub294 SSH \uc11c\ubc84\uac00 \uc124\uce58\ub418\uc5b4 \uc788\uc9c0 \uc54a\uc2b5\ub2c8\ub2e4.<br>By default, Xubuntu does not come with an SSH server installed.<br>\u2714\ufe0f \ud130\ubbf8\ub110\uc744 \uc5f4\uace0 \uc544\ub798 \uba85\ub839\uc5b4\ub85c \uc124\uce58\ud558\uc138\uc694<br>Open the terminal and install using the command below.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo apt update\nsudo apt install openssh-server<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">2.\u00a0<strong>SSH \uc11c\ube44\uc2a4 \uc2dc\uc791 \ubc0f \uc790\ub3d9 \uc2dc\uc791 \uc124\uc815<\/strong> <br>Start SSH service and configure it to start automatically.<\/h2>\n\n\n\n<p>\u2714\ufe0f \uc124\uce58 \ud6c4 SSH \uc11c\ube44\uc2a4\uac00 \uc790\ub3d9\uc73c\ub85c \uc2e4\ud589\ub418\uc9c0 \uc54a\ub294 \uacbd\uc6b0 \uc544\ub798\ucc98\ub7fc \uc2e4\ud589\ud558\uace0 \ubd80\ud305 \uc2dc \uc790\ub3d9\uc73c\ub85c \uc2dc\uc791\ub418\uac8c \uc124\uc815\ud569\ub2c8\ub2e4.<br>If the SSH service does not start automatically after installation, start it as shown below and configure it to launch automatically upon boot.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo systemctl enable --now ssh<\/code><\/pre>\n\n\n\n<p>\u2714\ufe0f \uc124\uce58 \ud6c4 \uc11c\ube44\uc2a4 \uc0c1\ud0dc \ud655\uc778\ud558\uae30<br>Checking the service status after installation<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo systemctl status ssh<\/code><\/pre>\n\n\n\n<p>\u2714\ufe0f <code>active (running)<\/code>\u00a0\uc0c1\ud0dc\uc774\uba74 SSH\uac00 \uc798 \uc2e4\ud589 \uc911\uc778 \uac83\uc785\ub2c8\ub2e4.<br>If the status is &#8220;active (running),&#8221; SSH is running correctly.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.\u00a0<strong>\ubc29\ud654\ubcbd \uc124\uc815 \/ Firewall Settings<\/strong> <strong>(UFW)<\/strong><\/h2>\n\n\n\n<p>\u2714\ufe0f UFW(Uncomplicated Firewall)\ub97c \uc0ac\uc6a9 \uc911\uc774\ub77c\uba74 SSH \uc5f0\uacb0\uc744 \ud5c8\uc6a9\ud574\uc918\uc57c \ud569\ub2c8\ub2e4<br>If you are using UFW (Uncomplicated Firewall), you need to allow SSH connections.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo ufw allow ssh<\/code><\/pre>\n\n\n\n<p>\u2714\ufe0f \uae30\ubcf8 SSH \ud3ec\ud2b8(22\ubc88)\uc5d0 \ub300\ud574 \ud5c8\uc6a9 \uc124\uc815\uc774 \uc0dd\uae41\ub2c8\ub2e4. \uc774\ud6c4 UFW\uac00 \ud65c\uc131\ud654\ub418\uc5b4 \uc788\uc73c\uba74 \uc678\ubd80\uc5d0\uc11c \uc811\uc18d\uc774 \uac00\ub2a5\ud574\uc9d1\ub2c8\ub2e4.<br>An allow rule is created for the default SSH port (port 22). Once UFW is enabled, external access becomes possible.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">4.\u00a0<strong>(\uc120\ud0dd) SSH \uc124\uc815 \ubcc0\uacbd<\/strong><br>(Optional) Change SSH settings<\/h2>\n\n\n\n<p>\u2714\ufe0f \uae30\ubcf8 \uc124\uc815\uc740 \ubcf4\ud1b5 \ubb38\uc81c \uc5c6\uc774 \ub3d9\uc791\ud558\uc9c0\ub9cc, \ud544\uc694\ud558\ub2e4\uba74 \uc124\uc815 \ud30c\uc77c\u00a0<code>\/etc\/ssh\/sshd_config<\/code>\u00a0\ub97c \ud3b8\uc9d1\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<br>The default settings usually work without issues, but you can edit the configuration file <code>\/etc\/ssh\/sshd_config<\/code> if necessary.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo nano \/etc\/ssh\/sshd_config<\/code><\/pre>\n\n\n\n<p>\u2714\ufe0f \uc608\ub97c \ub4e4\uc5b4\u00a0<strong>root \uacc4\uc815 \uc811\uc18d \ud5c8\uc6a9<\/strong>\uc744 \ubc14\uafb8\uac70\ub098\u00a0<strong>\ud3ec\ud2b8 \ubcc0\uacbd<\/strong>\u00a0\ub4f1\uc744 \ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \ubcc0\uacbd \ud6c4\uc5d0\ub294 \uc11c\ube44\uc2a4 \uc7ac\uc2dc\uc791\ud569\ub2c8\ub2e4.<br>For example, you can modify settings such as <strong>allowing root account access <\/strong>or <strong>changing the port<\/strong>. After making the changes, restart the service.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>sudo systemctl restart ssh<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">5.\u00a0<strong>\uc811\uc18d \ud14c\uc2a4\ud2b8<\/strong><br>Connection Test<\/h2>\n\n\n\n<p>\u2714\ufe0f \ub2e4\ub978 \ucef4\ud4e8\ud130\uc5d0\uc11c \ub2e4\uc74c\ucc98\ub7fc \uc811\uc18d\ud574 \ubd05\ub2c8\ub2e4<br>Try connecting from another computer as follows<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>ssh username@Xubuntu_IP address<\/code><\/pre>\n\n\n\n<p>\u2b50\ufe0f \uc11c\ubc84\uc758 \uc544\uc774\ud53c \uc8fc\uc18c\ub294 \ub2e4\uc74c\uacfc \uac19\uc774 \ud655\uc778 \ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<br>You can check the server&#8217;s IP address as follows.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>ip a<\/code><\/pre>\n\n\n\n<p>\ub610\ub294 \/ or<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>hostname -I<\/code><\/pre>\n\n\n\n<p>\u2b50\ufe0f \ud574\ub2f9 \uc544\uc774\ud53c \uc8fc\uc18c\uc5d0 \uc5f0\uacb0\ub418\ub294\uc9c0 \ud655\uc778 \ud558\ub824\uba74 \uc544\ub798\ucc98\ub7fc ping\uc744 \uc0ac\uc6a9\ud558\uc2dc\uba74\ub429\ub2c8\ub2e4.<br>To check if you can connect to the IP address, you can use the <code>ping<\/code> command as shown below.<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>ping IPAddresss<\/code><\/pre>\n\n\n\n<p>\u2714\ufe0f \ub9e5\uc5d0\uc11c \ub9ac\ub205\uc2a4\uc5d0 \ud130\ubbf8\ub110\ub85c \uc811\uc18d\ud558\uae30<br>Connecting to Linux via Terminal from a Mac<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"682\" src=\"https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/ssh-jpg.jpg\" alt=\"\" class=\"wp-image-6036\" srcset=\"https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/ssh-jpg.jpg 800w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/ssh-jpg-300x256.jpg 300w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/ssh-jpg-768x655.jpg 768w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/ssh-jpg-400x341.jpg 400w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption class=\"wp-element-caption\">SSH<\/figcaption><\/figure>\n\n\n\n<p>\u2714\ufe0f \ub9e5\uc5d0\uc11c sftp\ub85c \ub9ac\ub205\uc2a4\uc5d0 \uc811\uc18d\ud558\uae30<br>Connecting to Linux via SFTP from a Mac<\/p>\n\n\n\n<figure class=\"wp-block-gallery has-nested-images columns-default is-cropped wp-block-gallery-1 is-layout-flex wp-block-gallery-is-layout-flex\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"570\" data-id=\"6042\" src=\"https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp1-jpg.jpg\" alt=\"\" class=\"wp-image-6042\" srcset=\"https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp1-jpg.jpg 800w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp1-jpg-300x214.jpg 300w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp1-jpg-768x547.jpg 768w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp1-jpg-400x285.jpg 400w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption class=\"wp-element-caption\">sftp1<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"574\" data-id=\"6041\" src=\"https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp2-jpg.jpg\" alt=\"\" class=\"wp-image-6041\" srcset=\"https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp2-jpg.jpg 800w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp2-jpg-300x215.jpg 300w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp2-jpg-768x551.jpg 768w, https:\/\/www.freelifemakers.org\/wordpress\/wp-content\/uploads\/2026\/06\/sftp2-jpg-400x287.jpg 400w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption class=\"wp-element-caption\">sftp2<\/figcaption><\/figure>\n<\/figure>\n\n\n\n<p>SFTP<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\ud83d\udc49\ud83c\udffb open ssh\ub294 \ub124\ud2b8\uc6cc\ud06c\ub97c \ud1b5\ud574 \ucef4\ud4e8\ud130\uc5d0 \uc548\uc804\ud558\uac8c \uc6d0\uaca9 \uc811\uc18d\ud560 \uc218 \uc788\ub3c4\ub85d \ud574\uc8fc\ub294 \uc624\ud508\uc18c\uc2a4 \ubcf4\uc548 \ud504\ub85c\uadf8\ub7a8\uc785\ub2c8\ub2e4.OpenSSH is an open-source security program that enables secure remote access to computers over a network. \ud83d\udc49\ud83c\udffb \uc608\uc804\uc5d0\ub294 telnet\uc774\ub098 ftp\ub97c \uc0ac\uc6a9\ud588\uc5c8\ub294\ub370 \ub124\ud2b8\uc6cc\ud06c \uc0c1\uc5d0\uc11c \ubaa8\ub4e0 \uc815\ubcf4\uac00 \ud3c9\ubb38\uc73c\ub85c \uc804\ub2ec \ub418\uae30\ub54c\ubb38\uc5d0 \ud574\ud0b9\uc758 \uc704\ud5d8\uc774 \uc788\uc2b5\ub2c8\ub2e4.In the past, Telnet or FTP was used, but these carry [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6,1],"tags":[],"class_list":["post-6016","post","type-post","status-publish","format-standard","hentry","category-linux","category-uncategorized","missing-thumbnail"],"_links":{"self":[{"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/posts\/6016","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/comments?post=6016"}],"version-history":[{"count":22,"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/posts\/6016\/revisions"}],"predecessor-version":[{"id":6043,"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/posts\/6016\/revisions\/6043"}],"wp:attachment":[{"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/media?parent=6016"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/categories?post=6016"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.freelifemakers.org\/wordpress\/index.php\/wp-json\/wp\/v2\/tags?post=6016"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}