whois(1) on Solnix vs Linux and the BSDs
On Solnix, whois is the illumos (BSD-derived) client at /usr/bin/whois. Most of its flags select a particular registry database (-a ARIN, -A APNIC, -r RIPE and so on). Linux whois uses many of the same letters for RIPE query modifiers, so a Linux script's flags can mean something else here.
The manual pages
What Solnix runs
A default Solnix system runs the illumos whois at /usr/bin/whois. /usr/ucb/whois is also shipped, but the bundle does not describe it. The Solnix page documents no environment variables and no configuration file.
Differences
| Compared with | Topic | What differs |
|---|---|---|
| Linux | single-letter flags mean different things | On Solnix, -a, -b, -g, -i, -l, -m and -r each pick a registry database. On Linux the same letters are RIPE-style query modifiers: -a searches mirrored databases, -l and -m return less or more specific objects, -i is an inverse search, -r disables recursive contact lookups.Source: Solnix whois(1) -a, -b, -g, -i, -l, -m, -r; Linux whois(1) OPTIONS -a, -b, -g, -i, -l, -m, -r |
| Linux | -I meaning | Solnix -I queries the IANA database. Linux -I queries whois.iana.org first and then follows its referral to the authoritative server. The Linux page warns that IANA then receives your complete query.Source: Solnix whois(1) -I; Linux whois(1) -I |
| FreeBSD | default server selection and referrals | FreeBSD starts at the IANA whois server and follows referrals by default. Solnix builds the server name from the query's TLD plus .whois-servers.net. For an IP address it uses ARIN. For anything else it falls back to whois.crsnic.net. Source: FreeBSD whois(1) DESCRIPTION; Solnix whois(1) -h |
| OpenBSD, NetBSD | gTLD server lookup | OpenBSD and NetBSD first try whois.nic.tld for newer generic TLDs, then fall back to appending .whois-servers.net. The Solnix page describes only the .whois-servers.net rule. Source: OpenBSD whois(1) -h; NetBSD whois(1) -h; Solnix whois(1) -h |
| all four | -R meaning | Solnix has no -R. FreeBSD -R follows referrals recursively. Linux -R disables referrals and forces the server's local copy. OpenBSD and NetBSD -R selects the Russian RIPN database, which is deprecated in favour of -c RU.Source: Solnix whois(1) SYNOPSIS; FreeBSD whois(1) -R; Linux whois(1) -R; OpenBSD whois(1) -R; NetBSD whois(1) -R |
| FreeBSD | -Q meaning | On Solnix, -Q skips the authoritative server lookup and has no effect when combined with other options. On FreeBSD, -Q means do not follow referrals, and it is the default when a server is given by an option or environment variable.Source: Solnix whois(1) -Q; FreeBSD whois(1) -Q |
| FreeBSD, OpenBSD | -S verbatim output | Solnix has no -S. FreeBSD and OpenBSD adjust simple queries by default and suppress some output, and -S sends the query and prints the output verbatim. The Solnix page does not say whether it adjusts queries.Source: FreeBSD whois(1) -S; OpenBSD whois(1) -S; Solnix whois(1) SYNOPSIS |
| FreeBSD, NetBSD | -P PeeringDB | Solnix has no -P. FreeBSD and NetBSD -P uses the PeeringDB database of AS numbers.Source: FreeBSD whois(1) -P; NetBSD whois(1) -P; Solnix whois(1) SYNOPSIS |
| Linux, OpenBSD, NetBSD | -d meaning | Solnix has no -d. OpenBSD and NetBSD -d uses the US Department of Defense (.MIL) database. Linux -d also returns the reverse DNS delegation object.Source: Solnix whois(1) SYNOPSIS; OpenBSD whois(1) -d; NetBSD whois(1) -d; Linux whois(1) -d |
| all four | -i target database | Solnix -i uses the Network Solutions registry (whois.networksolutions.com). NetBSD -i does the same. FreeBSD and OpenBSD -i use InterNIC (whois.internic.net). Linux -i is an inverse attribute search.Source: Solnix whois(1) -i; NetBSD whois(1) -i; FreeBSD whois(1) -i; OpenBSD whois(1) -i; Linux whois(1) -i |
| OpenBSD, NetBSD | -k and -b availability | Solnix has -k (KRNIC) and -b (Network Abuse Clearinghouse). Neither OpenBSD nor NetBSD documents them. OpenBSD also lacks -f (AfriNIC), which Solnix, FreeBSD and NetBSD have.Source: Solnix whois(1) -k, -b, -f; OpenBSD whois(1) SYNOPSIS; NetBSD whois(1) SYNOPSIS |
| Linux, FreeBSD | environment and config file | Linux reads WHOIS_SERVER, WHOIS_OPTIONS and /etc/whois.conf. FreeBSD reads WHOIS_SERVER, then RA_SERVER, then defaults to whois.iana.org. The Solnix page documents no environment variables or config file. OpenBSD and NetBSD -p reads the whois port from /etc/services; Solnix defaults to 43.Source: Linux whois(1) ENVIRONMENT, NOTES; FreeBSD whois(1) ENVIRONMENT; OpenBSD whois(1) -p; NetBSD whois(1) -p; Solnix whois(1) -p |
Standards
- POSIX: whois is not a POSIX.1-2024 utility.
- Solnix: The page has no STANDARDS section. SEE ALSO cites NICNAME/WHOIS, RFC 812 (1 March 1982).
- Linux: SEE ALSO cites RFC 3912: WHOIS Protocol Specification.
- FreeBSD: STANDARDS cites NICNAME/WHOIS, RFC 954 (October 1985), and WHOIS Protocol Specification, RFC 3912 (September 2004).
- OpenBSD: STANDARDS cites RFC 954 (October 1985) and RFC 3912 (September 2004).
- NetBSD: STANDARDS cites RFC 954 (October 1985) and RFC 3912 (September 2004).
Writing portable scripts
- Do not rely on single-letter database flags in portable scripts:
-a,-i,-r,-R,-Iand-ddiffer between Solnix, Linux and the BSDs. Use-hhost with an explicit server instead. - Do not parse whois output for fields that vary by server. The default server choice differs between Solnix, FreeBSD and Linux, so pass
-hto get consistent results.
Every difference here is taken from the manual pages linked above: Solnix's published page, Linux (man-pages and the GNU and util-linux manuals), FreeBSD, OpenBSD and NetBSD. Each row names its source. Where a manual is silent, this page is too. Compiled 2026-10-26. Found a mistake? Mail hackers@lists.solnix.io.