383

Port 383/tcp is registered with IANA as hp-alarm-mgr with the description "hp performance data alarm manager" (lowercase, verbatim), assignee Frank Blakely (HP), and a blank reference field (dual-registered on TCP and UDP). It is the alarm-generation component of HP's performance-monitoring stack — HP OpenView, MeasureWare, and the HP Performance Agent. The port sits in a contiguous HP performance-monitoring block: 381 hp-collector ("hp performance data collector"), 382 hp-managed-node ("hp performance data managed node"), and 383 hp-alarm-mgr ("hp performance data alarm manager"). HP Performance Agent documentation references hp-alarm-mgr on 383/tcp and instructs administrators to enable port 383 and configure HTTP(S) so the Performance Agent can communicate across a firewall, recommending the default 383 be left unchanged; HP OpenView was HP's enterprise IT-infrastructure and network/systems-management suite of the 1990s and 2000s, since rebranded, sold off, and discontinued. The IANA reference field is blank. Security-wise this is enterprise monitoring legacy: an open 383 indicates HP OpenView or Performance Agent infrastructure and is an internal management surface, and secondary sources note historical vulnerabilities in the HP performance and alarm components (including arbitrary-file-deletion exploits referenced for port 383 and buffer-overflow issues in related HP OpenView Network Node Manager alarm services); since the product line is discontinued there is usually no good reason to leave 381–383 open. For an analyst, an open 383 means HP OpenView/Performance monitoring infrastructure, an internal-only management surface that on a modern network should be treated as legacy to be retired or firewalled.

IANA assignment

hp-alarm-mgr — "hp performance data alarm manager" (verbatim, lowercase); reference (blank — no RFC cited in IANA registry); assignee Frank Blakely (HP); dual-registered 383/tcp + 383/udp [IANA-assigned] — IANA Service Name and Transport Protocol Port Number Registry

Range class

well-known (0–1023)

Prevalence

nmap-services open-frequency ~0.000013 (de-facto) [Well-established] — nmap-services file

Related ports

381 (hp-collector), 382 (hp-managed-node), other HP OpenView ports

Primary use

alarm generation for HP performance monitoring (HP OpenView / MeasureWare / Performance Agent)

Other/unofficial uses

none beyond the HP OpenView ecosystem [Well-established]

Security implications

enterprise monitoring legacy; internal management surface; historical HP OpenView/alarm component vulnerabilities; product line discontinued [Well-established/Threat-reported]

Typically seen on

HP OpenView / Performance Agent management stations

Analyst note

An open 383 = HP OpenView/Performance monitoring infrastructure — internal management only; on a modern network treat as legacy to retire/firewall.

Port 383/udp carries hp-alarm-mgr, the HP Performance Data Alarm Manager component of the discontinued HP OpenView management suite; it should not be found open on internet-facing hosts today, and a responsive instance almost always signals a stale legacy management service rather than an intentionally exposed one.

IANA registers 383 as hp-alarm-mgr — "hp performance data alarm manager" — with Frank Blakely listed as assignee and contact, dually registered on both 383/tcp and 383/udp. The registry's reference field is blank; no RFC documents the protocol, so none should be cited.

Functionally, the service relayed performance-alarm status, threshold events, and alerts between managed nodes and an HP OpenView (later HP Operations Manager) management server. HP OpenView was a widely deployed enterprise network/systems-management product line in the 1990s–2000s but has since been discontinued, so the port is now essentially of historical interest only.

Because the parent product line is dead, an open 383/udp on a modern host is most plausibly a forgotten legacy install, a misconfiguration, or — on an internet-facing box — an anomaly worth investigating rather than a normally expected service. No dated IANA assignment record was available, and none is invented here.

IANA assignment

hp-alarm-mgr — "hp performance data alarm manager"; reference blank; assignee/contact Frank Blakely; dual-registered 383/tcp + 383/udp [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml

Range class

well-known (0–1023) [Confirmed] — IANA port ranges convention

Prevalence

Unknown — no nmap-services open-frequency figure for 383/udp was located in this research pass [Unknown]

Related ports

383/tcp (dual registration of the same service name) [Confirmed] — https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml

Primary use

HP Performance Data Alarm Manager, part of the legacy/discontinued HP OpenView (later HP Operations Manager) enterprise management suite, relaying performance-alarm status and threshold events between managed nodes and the management server [Likely] — https://www.cbtnuggets.com/common-ports/what-are-ports-381-383, https://en.wikipedia.org/wiki/HP_OpenView_Storage_Area_Manager

Other/unofficial uses

none credibly reported; no games, P2P, or other community-sourced applications found using this port beyond the HP OpenView attribution

Security implications

essentially never legitimately open today given the discontinued parent product; an unverified secondary-source claim links ports 381-383 to an "arbitrary file deletion" exploit but no CVE/advisory substantiates it

Typically seen on

legacy HP OpenView / HP Operations Manager management nodes; otherwise an anomaly or decommissioned host

Analyst note

treat an open 383/udp as a legacy HP OpenView signature or misconfiguration rather than a normal service; investigate rather than assume.