Appendix C. Common Ports

The following tables list the most common communication ports used by services, daemons, and programs included in Red Hat Enterprise Linux. This listing can also be found in the /etc/services file. For the official list of Well Known, Registered, and Dynamic ports as designated by the Internet Assigned Numbers Authority (IANA), refer to the following URL:


The Layer, where listed, denotes whether the service or protocol uses TCP or UDP for transport. If not listed, the service/protocol can use both TCP and UDP.

Port # / LayerNameComment
1 tcpmux TCP port service multiplexer
5 rje Remote Job Entry
7 echo Echo service
9 discard Null service for connection testing
11 systat System Status service for listing connected ports
13 daytime Sends date and time to requesting host
17 qotd Sends quote of the day to connected host
18 msp Message Send Protocol
19 chargen Character Generation service; sends endless stream of characters
20 ftp-data FTP data port
21 ftp File Transfer Protocol (FTP) port; sometimes used by File Service Protocol (FSP)
22 ssh Secure Shell (SSH) service
23 telnet The Telnet service
25 smtp Simple Mail Transfer Protocol (SMTP)
37 time Time Protocol
39 rlp Resource Location Protocol
42 nameserver Internet Name Service
43 nicname WHOIS directory service
49 tacacs Terminal Access Controller Access Control System for TCP/IP based authentication and access
50 re-mail-ck Remote Mail Checking Protocol
53 domain domain name services (such as BIND)
63 whois++ WHOIS++, extended WHOIS services
67 bootps Bootstrap Protocol (BOOTP) services; also used by Dynamic Host Configuration Protocol (DHCP) services
68 bootpc Bootstrap (BOOTP) client; also used by Dynamic Host Control Protocol (DHCP) clients
69 tftp Trivial File Transfer Protocol (TFTP)
70 gopher Gopher Internet document search and retrieval
71 netrjs-1 Remote Job Service
72 netrjs-2 Remote Job Service
73 netrjs-3 Remote Job Service
73 netrjs-4 Remote Job Service
79 finger Finger service for user contact information
80 http HyperText Transfer Protocol (HTTP) for World Wide Web (WWW) services
88 kerberos Kerberos network authentication system
95 supdup Telnet protocol extension
101 hostname Hostname services on SRI-NIC machines
102 iso-tsap ISO Development Environment (ISODE) network applications
105 csnet-ns Mailbox nameserver; also used by CSO nameserver
107 rtelnet Remote Telnet
109 pop2 Post Office Protocol version 2
110 pop3 Post Office Protocol version 3
111 sunrpc Remote Procedure Call (RPC) Protocol for remote command execution, used by Network Filesystem (NFS)
113 auth Authentication and Ident protocols
115 sftp Secure File Transfer Protocol (SFTP) services
117 uucp-path Unix-to-Unix Copy Protocol (UUCP) Path services
119 nntp Network News Transfer Protocol (NNTP) for the USENET discussion system
123 ntp Network Time Protocol (NTP)
137 netbios-ns NETBIOS Name Services used in Red Hat Enterprise Linux by Samba
138 netbios-dgm NETBIOS Datagram Services used in Red Hat Enterprise Linux by Samba
139 netbios-ssn NETBIOS Session Services used in Red Hat Enterprise Linux by Samba
143 imap Internet Message Access Protocol (IMAP)
161 snmp Simple Network Management Protocol (SNMP)
162 snmptrap Traps for SNMP
163 cmip-man Common Management Information Protocol (CMIP)
164 cmip-agent Common Management Information Protocol (CMIP)
174 mailq MAILQ
177 xdmcp X Display Manager Control Protocol
178 nextstep NeXTStep window server
179 bgp Border Gateway Protocol
191 prospero Cliffod Neuman's Prospero services
194 irc Internet Relay Chat (IRC)
199 smux SNMP UNIX Multiplexer
201 at-rtmp AppleTalk routing
202 at-nbp AppleTalk name binding
204 at-echo AppleTalk echo
206 at-zis AppleTalk zone information
209 qmtp Quick Mail Transfer Protocol (QMTP)
210 z39.50 NISO Z39.50 database
213 ipx Internetwork Packet Exchange (IPX), a datagram protocol commonly used in Novell Netware environments
220 imap3 Internet Message Access Protocol version 3
245 link LINK
347 fatserv Fatmen Server
363 rsvp_tunnel RSVP Tunnel
369 rpc2portmap Coda filesystem portmapper
370 codaauth2 Coda filesystem authentication services
372 ulistproc UNIX Listserv
389 ldap Lightweight Directory Access Protocol (LDAP)
427 svrloc Service Location Protocol (SLP)
434 mobileip-agent Mobile Internet Protocol (IP) agent
435 mobilip-mn Mobile Internet Protocol (IP) manager
443 https Secure Hypertext Transfer Protocol (HTTP)
444 snpp Simple Network Paging Protocol
445 microsoft-ds Server Message Block (SMB) over TCP/IP
464 kpasswd Kerberos password and key changing services
468 photuris Photuris session key management protocol
487 saft Simple Asynchronous File Transfer (SAFT) protocol
488 gss-http Generic Security Services (GSS) for HTTP
496 pim-rp-disc Rendezvous Point Discovery (RP-DISC) for Protocol Independent Multicast (PIM) services
500 isakmp Internet Security Association and Key Management Protocol (ISAKMP)
535 iiop Internet Inter-Orb Protocol (IIOP)
538 gdomap GNUstep Distributed Objects Mapper (GDOMAP)
546 dhcpv6-client Dynamic Host Configuration Protocol (DHCP) version 6 client
547 dhcpv6-server Dynamic Host Configuration Protocol (DHCP) version 6 Service
554 rtsp Real Time Stream Control Protocol (RTSP)
563 nntps Network News Transport Protocol over Secure Sockets Layer (NNTPS)
565 whoami whoami
587 submission Mail Message Submission Agent (MSA)
610 npmp-local Network Peripheral Management Protocol (NPMP) local / Distributed Queueing System (DQS)
611 npmp-gui Network Peripheral Management Protocol (NPMP) GUI / Distributed Queueing System (DQS)
612 hmmp-ind HMMP Indication / DQS
631 ipp Internet Printing Protocol (IPP)
636 ldaps Lightweight Directory Access Protocol over Secure Sockets Layer (LDAPS)
674 acap Application Configuration Access Protocol (ACAP)
694 ha-cluster Heartbeat services for High-Availability Clusters
749 kerberos-adm Kerberos version 5 (v5) 'kadmin' database administration
750 kerberos-iv Kerberos version 4 (v4) services
765 webster Network Dictionary
767 phonebook Network Phonebook
873 rsync rsync file transfer services
992 telnets Telnet over Secure Sockets Layer (TelnetS)
993 imaps Internet Message Access Protocol over Secure Sockets Layer (IMAPS)
994 ircs Internet Relay Chat over Secure Sockets Layer (IRCS)
995 pop3s Post Office Protocol version 3 over Secure Sockets Layer (POP3S)

Table C-1. Well Known Ports

The following ports are UNIX-specific and cover services ranging from email to authentication and more. Names enclosed in brackets (for example, [service]) are either daemon names for the service or common alias(es).

Port # / LayerNameComment
512/tcp exec Authentication for remote process execution
512/udp biff [comsat] Asynchrous mail client (biff) and service (comsat)
513/tcp login Remote Login (rlogin)
513/udp who [whod] who logged user listing
514/tcp shell [cmd] remote shell (rshell) and remote copy (rcp) with no logging
514/udp syslog UNIX system logging service
515 printer [spooler] line printer (lpr) spooler
517/udp talk talk remote calling service and client
518/udp ntalk Network talk (ntalk) remote calling service and client
519 utime [unixtime] UNIX time (utime) protocol
520/tcp efs Extended Filename Server (EFS)
520/udp router [route, routed] Routing Information Protocol (RIP)
521 ripng Routing Information Protocol for Internet Protocol version 6 (IPv6)
525 timed [timeserver] Time daemon (timed)
526/tcp tempo [newdate] Tempo
530/tcp courier [rpc] Courier Remote Procedure Call (RPC) protocol
531/tcp conference [chat] Internet Relay Chat
532 netnews Netnews
533/udp netwall Netwall for emergency broadcasts
540/tcp uucp [uucpd] Unix-to-Unix copy services
543/tcp klogin Kerberos version 5 (v5) remote login
544/tcp kshell Kerberos version 5 (v5) remote shell
548 afpovertcp Appletalk Filing Protocol (AFP) over Transmission Control Protocol (TCP)
556 remotefs [rfs_server, rfs] Brunhoff's Remote Filesystem (RFS)

Table C-2. UNIX Specific Ports

Table C-3 lists ports submitted by the network and software community to the IANA for formal registration in the port number list.

Port # / LayerNameComment
1080 socks SOCKS network application proxy services
1236 bvcontrol [rmtcfg] Garcilis Packeten Remote Configuration Server[a]
1300 h323hostcallsc H.323 teleconferencing Host Call Secure
1433 ms-sql-s Microsoft SQL Server
1434 ms-sql-m Microsoft SQL Monitor
1494 ica Citrix ICA Client
1512 wins Microsoft Windows Internet Name Server
1524 ingreslock Ingres Database Management System (DBMS) lock services
1525 prospero-np Prospero non-priveleged
1645 datametrics [old-radius] Datametrics / old radius entry
1646 sa-msg-port [oldradacct] sa-msg-port / old radacct entry
1649 kermit Kermit file transfer and management service
1701 l2tp [l2f] Layer 2 Tunneling Protocol (LT2P) / layer 2 forwarding (L2F)
1718 h323gatedisc H.323 telecommunication Gatekeeper Discovery
1719 h323gatestat H.323 telecommunication Gatekeeper Status
1720 h323hostcall H.323 telecommunication Host Call setup
1758 tftp-mcast Trivial FTP Multicast
1759 mtftp Multicast Trivial FTP (MTFTP)
1789 hello Hello router communication protocol
1812 radius Radius dial-up authentication and accounting services
1813 radius-acct Radius Accounting
1911 mtp Starlight Networks Multimedia Transport Protocol (MTP)
1985 hsrp Cisco Hot Standby Router Protocol
1986 licensedaemon Cisco License Management Daemon
1997 gdp-port Cisco Gateway Discovery Protocol (GDP)
2049 nfs [nfsd] Network File System (NFS)
2102 zephyr-srv Zephyr notice transport and delivery Server
2103 zephyr-clt Zephyr serv-hm connection
2104 zephyr-hm Zephyr host manager
2401 cvspserver Concurrent Versions System (CVS) client/server operations
2430/tcp venus Venus cache manager for Coda file system (codacon port)
2430/udp venus Venus cache manager for Coda file system (callback/wbc interface)
2431/tcp venus-se Venus Transmission Control Protocol (TCP) side effects
2431/udp venus-se Venus User Datagram Protocol (UDP) side effects
2432/udp codasrv Coda file system server port
2433/tcp codasrv-se Coda file system TCP side effects
2433/udp codasrv-se Coda file system UDP SFTP side effect
2600 hpstgmgr [zebrasrv] HPSTGMGR; Zebra routing[b]
2601 discp-client [zebra] discp client; Zebra integrated shell
2602 discp-server [ripd] discp server; Routing Information Protocol daemon (ripd)
2603 servicemeter [ripngd] Service Meter; RIP daemon for IPv6
2604 nsc-ccs [ospfd] NSC CCS; Open Shortest Path First daemon (ospfd)
2605 nsc-posa NSC POSA; Border Gateway Protocol daemon (bgpd)
2606 netmon [ospf6d] Dell Netmon; OSPF for IPv6 daemon (ospf6d)
2809 corbaloc Common Object Request Broker Architecture (CORBA) naming service locator
3130 icpv2 Internet Cache Protocol version 2 (v2); used by Squid Proxy caching server
3306 mysql MySQL database service
3346 trnsprntproxy Trnsprnt Proxy
4011 pxe Pre-execution Environment (PXE) service
4321 rwhois Remote Whois (rwhois) service
4444 krb524 Kerberos version 5 (v5) to version 4 (v4) ticket translator
5002 rfe Radio Free Ethernet (RFE) audio broadcasting system
5308 cfengine Configuration Engine (Cfengine)
5999 cvsup [CVSup] CVSup file transfer and update tool
6000 x11 [X] X Window System services
7000 afs3-fileserver Andrew File System (AFS) file server
7001 afs3-callback AFS port for callbacks to cache manager
7002 afs3-prserver AFS user and group database
7003 afs3-vlserver AFS volume location database
7004 afs3-kaserver AFS Kerberos authentication service
7005 afs3-volser AFS volume management server
7006 afs3-errors AFS error interpretation service
7007 afs3-bos AFS basic overseer process
7008 afs3-update AFS server-to-server updater
7009 afs3-rmtsys AFS remote cache manager service
9876 sd Session Director
10080 amanda Advanced Maryland Automatic Network Disk Archiver (Amanda) backup services
11371 pgpkeyserver Pretty Good Privacy (PGP) / GNU Privacy Guard (GPG) public keyserver
11720 h323callsigalt H.323 Call Signal Alternate
13720 bprd Veritas NetBackup Request Daemon (bprd)
13721 bpdbm Veritas NetBackup Database Manager (bpdbm)
13722 bpjava-msvc Veritas NetBackup Java / Microsoft Visual C++ (MSVC) Protocol
13724 vnetd Veritas Network Utility
13782 bpcd Vertias NetBackup
13783 vopied Veritas VOPIED Protocol
22273 wnn6 [wnn4] Kana/Kanji conversion system[c]
26000 quake Quake (and related) multi-player game servers
26208 wnn6-ds  
33434 traceroute Traceroute network tracking tool
a. Comment from /etc/services: "Port 1236 is registered as `bvcontrol', but is also used by the Gracilis Packeten remote config server. The official name is listed as the primary name, with the unregistered name as an alias."
b. Note from /etc/services: "Ports numbered 2600 through 2606 are used by the zebra package without being registered. The primary names are the registered names, and the unregistered names used by zebra are listed as aliases."
c. Note from /etc/services: "This port is registered as wnn6, but also used under the unregistered name 'wnn4' by the FreeWnn package."

Table C-3. Registered Ports

Table C-4 shows a list of ports related to Datagram Delivery Protocol (DDP) used on AppleTalk networks.

Port # / LayerNameComment
1/ddp rtmp Routing Table Management Protocol
2/ddp nbp Name Binding Protocol
4/ddp echo AppleTalk Echo Protocol
6/ddp zip Zone Information Protocol

Table C-4. Datagram Deliver Protocol Ports

Table C-5 is a listing of ports related to the Kerberos network authentication protocol. Where noted, v5 refers to Kerberos version 5 protocol. Note that these ports are not registered with the IANA.

Port # / LayerNameComment
751 kerberos_master Kerberos authentication
752 passwd_server Kerberos Password (kpasswd) server
754 krb5_prop Kerberos v5 slave propagation
760 krbupdate [kreg] Kerberos registration
1109 kpop Kerberos Post Office Protocol (KPOP)
2053 knetd Kerberos de-multiplexor
2105 eklogin Kerberos v5 encrypted remote login (rlogin)

Table C-5. Kerberos (Project Athena/MIT) Ports

Table C-6 is a listing of unregistered ports that are used by services and protocols that may be installed on your Red Hat Enterprise Linux system or is necessary for communication between Red Hat Enterprise Linux and systems running other operating systems.

Port # / LayerNameComment
15/tcp netstat Network Status (netstat)
98/tcp linuxconf Linuxconf Linux administration tool
106 poppassd Post Office Protocol Password change daemon (POPPASSD)
465/tcp smtps Simple Mail Transfer Protocol over Secure Sockets Layer (SMTPS)
616/tcp gii Gated (routing daemon) Interactive Interface
808 omirr [omirrd] Online Mirror (Omirr) file mirroring services
871/tcp supfileserv Software Upgrade Protocol (SUP) server
901/tcp swat Samba Web Administration Tool (SWAT)
953 rndc Berkeley Internet Name Domain version 9 (BIND 9) remote name daemon configuration tool
1127 sufiledbg Software Upgrade Protocol (SUP) debugging
1178/tcp skkserv Simple Kana to Kanji (SKK) Japanese input server
1313/tcp xtel French Minitel text information system
1529/tcp support [prmsd, gnatsd] GNATS bug tracking system
2003/tcp cfinger GNU Finger
2150 ninstall Network Installation Service
2988 afbackup afbackup client-server backup system
3128/tcp squid Squid Web proxy cache
3455 prsvp RSVP port
5432 postgres PostgreSQL database
4557/tcp fax FAX transmission service (old service)
4559/tcp hylafax HylaFAX client-server protocol (new service)
5232 sgi-dgl SGI Distributed Graphics Library
5354 noclog NOCOL network operation center logging daemon (noclogd)
5355 hostmon NOCOL network operation center host monitoring
5680/tcp canna Canna Japanese character input interface
6010/tcp x11-ssh-offset Secure Shell (SSH) X11 forwarding offset
6667 ircd Internet Relay Chat daemon (ircd)
7100/tcp xfs X Font Server (XFS)
7666/tcp tircproxy Tircproxy IRC proxy service
8008 http-alt Hypertext Tranfer Protocol (HTTP) alternate
8080 webcache World Wide Web (WWW) caching service
8081 tproxy Transparent Proxy
9100/tcp jetdirect [laserjet, hplj] Hewlett-Packard (HP) JetDirect network printing service
9359 mandelspawn [mandelbrot] Parallel Mandelbrot spawning program for the X Window System
10081 kamanda Amanda backup service over Kerberos
10082/tcp amandaidx Amanda backup services
10083/tcp amidxtape Amanda backup services
20011 isdnlog Integrated Systems Digital Network (ISDN) logging system
20012 vboxd ISDN voice box daemon (vboxd)
22305/tcp wnn4_Kr kWnn Korean input system
22289/tcp wnn4_Cn cWnn Chinese input system
22321/tcp wnn4_Tw tWnn Chinese input system (Taiwan)
24554 binkp Binkley TCP/IP Fidonet mailer daemon
27374 asp Address Search Protocol
60177 tfido Ifmail FidoNet compatible mailer service
60179 fido FidoNet electronic mail and news network

Table C-6. Unregistered Ports