{"id":3742,"date":"2026-10-21T11:41:37","date_gmt":"2026-10-21T09:41:37","guid":{"rendered":"https:\/\/ahassan.inscastellbisbal.net\/?page_id=3742"},"modified":"2026-10-21T11:42:43","modified_gmt":"2026-10-21T09:42:43","slug":"protocol-darrencada-de-totes-les-mvs-des-de-cli","status":"publish","type":"page","link":"https:\/\/ahassan.inscastellbisbal.net\/?page_id=3742","title":{"rendered":"Protocol d&#8217;arrencada de totes les MVs des de CLI"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\">1. Per qu\u00e8 conv\u00e9 disposar d&#8217;un usuari propi amb privilegis i intercanvi de claus SSH en lloc d&#8217;utilitzar <code>root<\/code>?<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Seguretat i minimitzaci\u00f3 d&#8217;atacs (Principi de m\u00ednim privilegi):<\/strong> Permetre l&#8217;acc\u00e9s directe com a <code>root<\/code> per SSH deixa el sistema exposat a atacs per for\u00e7a bruta. Si desactives <code>PermitRootLogin<\/code> a la configuraci\u00f3 d&#8217;SSH i utilitzes un usuari propi amb permisos administratius (via <code>sudo<\/code>), afegeixes una cap addicional de protecci\u00f3.<\/li>\n\n\n\n<li><strong>Autenticaci\u00f3 segura sense contrasenya (Intercanvi de claus SSH):<\/strong> L&#8217;\u00fas de claus p\u00fablica\/privada elimina la necessitat d&#8217;enviar contrasenyes per la xarxa i evita l&#8217;\u00fas de textos en pla o scripts automatitzats amb contrasenyes emmagatzemades. Aix\u00f2 permet automatitzar tasques o scripts d&#8217;administraci\u00f3 de manera totalment segura.<\/li>\n\n\n\n<li><strong>Tra\u00e7abilitat i auditoria d&#8217;accions:<\/strong> Si diversos administradors accedeixen directament com a <code>root<\/code>, \u00e9s molt dif\u00edcil saber quin usuari ha executat cada comanda en els registres (<code>logs<\/code>). En accedir amb un usuari propi i utilitzar <code>sudo<\/code>, qualsevol acci\u00f3 administrativa queda registrada associada a la identitat d&#8217;aquell usuari.<\/li>\n\n\n\n<li><strong>Prevenci\u00f3 d&#8217;errors humans accidencials:<\/strong> Treballar de manera continuada com a <code>root<\/code> augmenta el risc d&#8217;executar comandes destructives per equivocaci\u00f3. Treballar amb un usuari est\u00e0ndard i fer servir <code>sudo<\/code> nom\u00e9s per a accions concretes obliga a ser conscient de quan s&#8217;estan aplicant canvis cr\u00edtics al sistema.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">2. Justificaci\u00f3 del procediment d&#8217;arrencada definit i l&#8217;ordre en qu\u00e8 s&#8217;engeguen les m\u00e0quines virtuals (MVs)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">L&#8217;ordre en qu\u00e8 s&#8217;arrenquen les m\u00e0quines virtuals en un entorn de xarxa\/servidors ha de seguir una <strong>jerarquia de depend\u00e8ncia de serveis<\/strong>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>1r \u2014 Serveis de Xarxa i Enrutament (Routers \/ Firewalls \/ Gateway):<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Justificaci\u00f3:<\/strong> Abans que qualsevol servidor o client pugui comunicar-se, la infraestructura de xarxa ha d&#8217;estar activa. Si no s&#8217;engega primer el router o gateway, la resta de MVs no tindran connectivitat ni assignaci\u00f3 d&#8217;IPs.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>2n \u2014 Serveis d&#8217;Infraestructura Base i Resoluci\u00f3 (DHCP, DNS, Directori Actiu\/LDAP):<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Justificaci\u00f3:<\/strong> Els servidors d&#8217;aplicaci\u00f3 i els clients necessiten resoldre noms de domini (DNS) i, en molts casos, obtenir una adre\u00e7a IP autom\u00e0tica (DHCP) per poder iniciar correctament els seus serveis.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>3r \u2014 Servidors de Bases de Dades i Magatzems de Dades:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Justificaci\u00f3:<\/strong> Les aplicacions web o d&#8217;empresa depenen de la base de dades. Si el servidor d&#8217;aplicacions s&#8217;engega abans que la base de dades estigui disponible, els serveis fallaran en intentar connectar-s&#8217;hi durant l&#8217;arrencada.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>4t \u2014 Servidors d&#8217;Aplicacions i Serveis Web (Web, Mail, App Servers):<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Justificaci\u00f3:<\/strong> Aquests serveis utilitzen la xarxa, el DNS i les bases de dades ja inicialitzades per funcionar correctament i respondre a les peticions dels usuaris.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>5\u00e8 \u2014 Clients \/ M\u00e0quines d&#8217;Usuari Final:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Justificaci\u00f3:<\/strong> S&#8217;engeguen en darrer lloc perqu\u00e8 quan l&#8217;usuari s&#8217;autentiqui o accedeixi als serveis de xarxa, tota la infraestructura estigui 100% operativa i no es produeixin errors de connexi\u00f3.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Pas 1: Crear l&#8217;usuari amb privilegis (<code>sudo<\/code>) a les MVs<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A cada una de les m\u00e0quines virtuals (o mitjan\u00e7ant un script si les crees d&#8217;inici), executa les comandes seg\u00fcents com a <code>root<\/code> per crear un usuari anomenat <code>adminuser<\/code> (pots canviar el nom pel que vulguis):<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code># 1. Crear l'usuari i la seva directori personal (-m)\nadduser adminuser\n\n# 2. Afegir l'usuari al grup amb permisos d'administraci\u00f3 (sudo o wheel segons la distribuci\u00f3)\n# En Debian\/Ubuntu:\nusermod -aG sudo adminuser\n\n# En RHEL\/CentOS\/Rocky:\n# usermod -aG wheel adminuser<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"421\" height=\"60\" src=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/VirtualBox_Rocky_21_10_2026_11_16_13.png\" alt=\"\" class=\"wp-image-3743\" srcset=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/VirtualBox_Rocky_21_10_2026_11_16_13.png 421w, https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/VirtualBox_Rocky_21_10_2026_11_16_13-300x43.png 300w\" sizes=\"auto, (max-width: 421px) 100vw, 421px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Perqu\u00e8 no demani contrasenya en executar comandes d&#8217;administraci\u00f3 (opcional per\u00f2 recomanat per a tasques d&#8217;automatitzaci\u00f3):<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>echo \"adminuser ALL=(ALL) NOPASSWD:ALL\" | sudo tee \/etc\/sudoers.d\/adminuser<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">Pas 2: Configurar l&#8217;intercanvi de claus SSH per a connexi\u00f3 autom\u00e0tica<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Des de la teva m\u00e0quina local \/ equip d&#8217;administraci\u00f3:<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li><strong>Generar la parella de claus SSH<\/strong> (si no en tens cap de creada):<\/li>\n<\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>ssh-keygen -t ed25519 -C \"adminuser@laboratori\"\n# Prem Enter a totes les preguntes per no assignar pasphrase si vols connexi\u00f3 100% automatitzada<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"739\" height=\"360\" src=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/VirtualBox_Rocky_21_10_2026_11_23_14.png\" alt=\"\" class=\"wp-image-3744\" srcset=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/VirtualBox_Rocky_21_10_2026_11_23_14.png 739w, https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/VirtualBox_Rocky_21_10_2026_11_23_14-300x146.png 300w\" sizes=\"auto, (max-width: 739px) 100vw, 739px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Copiar la clau p\u00fablica a cadascuna de les MVs<\/strong>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">ssh-copy-id adminuser@IP_DE_LA_MV<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Comprovar la connexi\u00f3 sense contrasenya<\/strong>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">ssh adminuser@IP_DE_LA_MV<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Pas 3: Script per arrencar el laboratori sencer des de la l\u00ednia de comandes<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Segons l&#8217;hipervisor que utilitzis (VirtualBox, KVM\/virsh, Proxmox, o Vagrant), pots utilitzar un script CLI per engegar totes les MVs en l&#8217;ordre adequat.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">opci\u00f3 A: VirtualBox (<code>VBoxManage<\/code>)<\/h4>\n\n\n\n<p class=\"wp-block-paragraph\">Crea un fitxer <code>arrencar_lab.sh<\/code><sup><\/sup>:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#!\/bin\/bash\n\necho \"Arrencant xarxa\/router...\"\nVBoxManage startvm \"MV_Router\" --type headless\nsleep 10\n\necho \"Arrencant serveis base (DNS\/DHCP)...\"\nVBoxManage startvm \"MV_DNS\" --type headless\nsleep 5\n\necho \"Arrencant Servidors...\"\nVBoxManage startvm \"MV_Server1\" --type headless\nVBoxManage startvm \"MV_Server2\" --type headless\n\necho \"Laboratori engegat correctament.\"<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"470\" height=\"403\" src=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/Screenshot-at-2026-10-21-11-31-33.png\" alt=\"\" class=\"wp-image-3745\" srcset=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/Screenshot-at-2026-10-21-11-31-33.png 470w, https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/Screenshot-at-2026-10-21-11-31-33-300x257.png 300w\" sizes=\"auto, (max-width: 470px) 100vw, 470px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Opci\u00f3 B: KVM \/ libvirt (<code>virsh<\/code>)<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#!\/bin\/bash\n\necho \"Iniciant MVs del laboratori...\"\nvirsh start MV_Router\nsleep 10\nvirsh start MV_DNS\nsleep 5\nvirsh start MV_Server1\nvirsh start MV_Server2\n\necho \"Estat actual de les MVs:\"\nvirsh list --all<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">Per donar permisos d&#8217;execuci\u00f3 i executar l&#8217;script:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>chmod +x arrencar_lab.sh<br>.\/arrencar_lab.sh<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"529\" height=\"267\" src=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/Screenshot-at-2026-10-21-11-32-30.png\" alt=\"\" class=\"wp-image-3746\" srcset=\"https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/Screenshot-at-2026-10-21-11-32-30.png 529w, https:\/\/ahassan.inscastellbisbal.net\/wp-content\/uploads\/2026\/10\/Screenshot-at-2026-10-21-11-32-30-300x151.png 300w\" sizes=\"auto, (max-width: 529px) 100vw, 529px\" \/><\/figure>\n\n\n<div class=\"wpforms-container wpforms-container-full wpforms-block wpforms-block-9c05cfd3-88d5-48f1-8539-118e045f91c7\" id=\"wpforms-764\"><form id=\"wpforms-form-764\" class=\"wpforms-validate wpforms-form\" data-formid=\"764\" method=\"post\" enctype=\"multipart\/form-data\" action=\"\/index.php?rest_route=%2Fwp%2Fv2%2Fpages%2F3742\" 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Per qu\u00e8 conv\u00e9 disposar d&#8217;un usuari propi amb privilegis i intercanvi de claus SSH en lloc d&#8217;utilitzar root? 2. Justificaci\u00f3 del procediment d&#8217;arrencada definit i l&#8217;ordre en qu\u00e8 s&#8217;engeguen les m\u00e0quines virtuals (MVs) L&#8217;ordre en qu\u00e8 s&#8217;arrenquen les m\u00e0quines virtuals en un entorn de xarxa\/servidors ha de seguir una [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":3496,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3742","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/pages\/3742","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3742"}],"version-history":[{"count":1,"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/pages\/3742\/revisions"}],"predecessor-version":[{"id":3748,"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/pages\/3742\/revisions\/3748"}],"up":[{"embeddable":true,"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=\/wp\/v2\/pages\/3496"}],"wp:attachment":[{"href":"https:\/\/ahassan.inscastellbisbal.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3742"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}