{"id":61,"date":"2025-03-19T13:54:38","date_gmt":"2025-03-19T13:54:38","guid":{"rendered":"https:\/\/vtom.uk\/?page_id=61"},"modified":"2025-04-02T14:24:29","modified_gmt":"2025-04-02T13:24:29","slug":"snmp","status":"publish","type":"page","link":"https:\/\/vtom.uk\/index.php\/snmp\/","title":{"rendered":"SNMP"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">SNMP remains one of, if not the most powerful protocols for monitoring network and infrastructure components. Defined in 1990 in <a href=\"https:\/\/datatracker.ietf.org\/doc\/html\/rfc1157\" target=\"_blank\" rel=\"noreferrer noopener\">RFC 1157<\/a>, it is a layer 7 protocol using UDP port 161 for requests &amp; responses, and UDP port 162 for notifications. There are three main versions (SNMPv1, SNMPv2c, SNMPv3), however v1 and v2c have severe security vulnerabilities and should be disabled in favour of v3.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignleft size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"256\" height=\"362\" src=\"https:\/\/vtom.uk\/wp-content\/uploads\/2025\/03\/image-12.png\" alt=\"\" class=\"wp-image-62\" style=\"width:125px;height:auto\" srcset=\"https:\/\/vtom.uk\/wp-content\/uploads\/2025\/03\/image-12.png 256w, https:\/\/vtom.uk\/wp-content\/uploads\/2025\/03\/image-12-212x300.png 212w\" sizes=\"auto, (max-width: 256px) 100vw, 256px\" \/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">Author Michael W Lucas describes it in his book &#8220;The Networknomicon, or SNMP Mastery&#8221; as &#8220;dark magic&#8221;.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Link to book: <a href=\"https:\/\/www.amazon.co.uk\/Networknomicon-SNMP-Mastery-Michael-Lucas\/dp\/1642350354\">Amazon<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SNMP features 3 components:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>SNMP Manager <\/strong>&#8211; This listens for notifications from, and sends requests to, the SNMP agent.<\/li>\n\n\n\n<li><strong>SNMP Agent <\/strong>&#8211; This runs on a network device such as a switch, router, firewall, UPS, printer, and so on, and communicates with the SNMP Manager.<\/li>\n\n\n\n<li><strong>MIB <\/strong>&#8211; The &#8220;Management Information Base&#8221; defines the dictionary and structure of data communicated between the manager and agent.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The following communication flows are exist within SNMP<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"479\" height=\"454\" src=\"https:\/\/vtom.uk\/wp-content\/uploads\/2025\/03\/image-13.png\" alt=\"\" class=\"wp-image-64\" srcset=\"https:\/\/vtom.uk\/wp-content\/uploads\/2025\/03\/image-13.png 479w, https:\/\/vtom.uk\/wp-content\/uploads\/2025\/03\/image-13-300x284.png 300w\" sizes=\"auto, (max-width: 479px) 100vw, 479px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A SNMP Trap Message is just an alert that informs the remote end (SNMP Manager) that a condition that was previously\u00a0set has been met, Such as informing the SNMP manager that a filesystem has reached a certain threshold.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>SNMP remains one of, if not the most powerful protocols for monitoring network and infrastructure components. Defined in 1990 in RFC 1157, it is a layer 7 protocol using UDP port 161 for requests &amp; responses, and UDP port 162 for notifications. There are three main versions (SNMPv1, SNMPv2c, SNMPv3), however v1 and v2c have &hellip; <a href=\"https:\/\/vtom.uk\/index.php\/snmp\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">SNMP<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-61","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/pages\/61","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/comments?post=61"}],"version-history":[{"count":2,"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/pages\/61\/revisions"}],"predecessor-version":[{"id":324,"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/pages\/61\/revisions\/324"}],"wp:attachment":[{"href":"https:\/\/vtom.uk\/index.php\/wp-json\/wp\/v2\/media?parent=61"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}