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Current border blocks
Ports
These are the current ports that are blocked at the border. Unless otherwise specified, blocks affect traffic in both directions.
| Destination Port | Service | Date added | Additional notes |
|---|---|---|---|
| 7/tcp, 7/udp | echo | Prior to 2000 | |
| 9/tcp, 9/udp | discard | Prior to 2000 | |
| 11/tcp, 11/udp | systat | April, 2020 | CHG0046078 |
| 17/tcp, 17/udp | qotd | April, 2020 | CHG0046078 |
| 19/tcp, 19/udp | chargen | Prior to 2000 | |
| 23/tcp | telnet | February, 2016 | inbound only |
| 37/tcp, 37/udp | time (not NTP)
|
April, 2020 | CHG0046078 |
| 42/tcp, 42,udp | nameserver | December, 2004 | |
| 49/tcp, 49/udp | tacacs | April, 2020 | CHG0046078 |
| 67/udp | bootps | August, 2000 | |
| 68/udp | bootpc | August, 2000 | |
| 69/udp | tftp | August, 2000 | |
| 88/tcp | Kerberos | April, 2020 | CHG0046078 |
| 88/udp | Kerberos | March, 2021 | CHG328248 (inbound only) |
| 111/tcp, 111/udp | sunrpc | Prior to 2000 | |
| 135/tcp, 135/udp | epmap | Prior to 2000 | |
| 137/tcp, 137/udp | netbios-ns | Prior to 2000 | |
| 138/tcp, 138/udp | netbios-dgm | Prior to 2000 | |
| 139/tcp, 139/udp | netbios-ssn | Prior to 2000 | |
| 161/tcp, 161/udp | SNMP | August, 2000 | |
| 162/tcp, 162/udp | SNMPtrap | August, 2000 | |
| 177/udp | XDMCP | November, 2019 | CHG0045312, made permanent with CHG0046078; 162.96.0.0/16 (Fairview) is NOT blocked |
| 389/tcp | LDAP | April, 2020 | CHG0046078; access to ldap.umn.edu is not blocked |
| 389/udp | LDAP | May, 2018 | CHG0042126 |
| 427/udp | SLP | June, 2023 | CHG1190975, makes a block of inbound Service Location Protocol permanent |
| 445/tcp, 445/udp | microsoft-ds | August, 2000 | |
| 514/udp | syslog | August, 2000 | Inbound only |
| 515/tcp | printer | August, 2000 | |
| 520/udp | rip | April, 2020 | CHG0046078 |
| 546/udp, 547/udp | DHCPv6 (client and server) | April, 2020 |
CHG0046078 |
| 548/udp | afpovertcp | August, 2000 | |
| 548/tcp | afpovertcp | September, 2002 | |
| 593/tcp | http-rpc-epmap | August, 2003 | inbound only |
| 623/tcp | ms-sql-s | May, 2018 | |
| 631/tcp, 631/udp | ipp | April, 2020 | CHG0046078 |
| 664/tcp | ms-sql-s | May, 2018 | |
| 1433/tcp | ms-sql-s | May, 2002 | |
| 1434/tcp, 1434/udp | ms-sql-m | January, 2003 | |
| 1521/tcp | September, 2002 | common Oracle listener; inbound only | |
| 1900/tcp, 1900/udp | upnp | January, 2002 | |
| 1993/tcp, 1993/udp | snmpmux | February, 2002 | |
| 2049/tcp, 2049/udp | nfsd | Prior to 2000 | |
| 2375/tcp, 2376/tcp, 2377/tcp | Docker ports | July, 2021 | TDX change 472738; inbound only |
| 2484/tcp | September, 2002 | common Oracle listener; inbound only | |
| 2701/tcp, 2702/tcp | Microsoft Configuration Manager remote control | March, 2021 | CHG328248 |
| 3283/udp | Apple remote desktop | April, 2020 | CHG0046078 |
| 3306/tcp | mysql | August, 2006 | inbound only |
| 3389/tcp, 3389/udp | rdp |
March, 2012 (tcp) June 2019 (udp) |
inbound only |
| 3702/udp | Web Services Dynamic Discovery (WS-Discovery) | August, 2019 | CHG0044707 (UIS #570851); made permanent with CHG0046078 |
| 4045/tcp, 4045/udp | lockd | Prior to 2000 | |
| 5353/udp | mDNS | April, 2020 | CHG0046078 (inbound only) |
| 5432/tcp | Postgresql | April, 2020 | CHG0046078 (inbound only) |
| 5900/tcp | VNC | March, 2020 | inbound only; CHG0045933; made permanent with CHG0046078 |
| 5985/tcp, 5986/tcp | WinRM | September, 2020 | inbound only; added temporarily in August, 2020; made permanent with change ID #138277 |
| 6000/tcp | x11 | August, 2006 | 162.96.0.0/16 (Fairview) is NOT blocked |
| 6379/tcp | redis | April, 2020 | CHG0046078 (inbound only) |
| 7001/tcp, 7001/udp | afs3-callback | October, 2018 | inbound only; CHG0042977 |
| 7002/tcp | afs3-prserver | October, 2018 | inbound only; CHG0042977 |
| 9100/tcp | jetdirect | April, 2016 | inbound only |
| 11211/udp | memcache | April, 2020 | inbound only; CHG0046078 |
| 16992/tcp | ms-sql-s | May, 2018 | |
| 16993/tcp | ms-sql-s | May, 2018 | |
| 16994/tcp | ms-sql-s | May, 2018 | |
| 16995/tcp | ms-sql-s | May, 2018 | |
| 27017/tcp | mongodb | April, 2020 | inbound only; CHG0046078 |
| 32771/tcp, 32771/udp | Prior to 2000 | common SunRPC | |
| 32772/tcp, 32772/udp | Prior to 2000 | common SunRPC |
Other items that are blocked
The U's border also blocks the following:
- RFC1918 address (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16)
- RFC 6598 address (100.64.0.0/10)
- Loopback (127.0.0.0/8)
- Directed broadcasts
- Classful Boundaries
- Inbound traffic with UMN source addresses (spoofed inbound)
- Outbound traffic without UMN source addresses (spoofed outbound)
- Source-routed traffic