---
name: "krlogin"
section: "1"
platform: "linux"
package: "kerberos4kth-clients"
version: "1.2.2-11.2"
release: "Debian 3.1 (Sarge)"
platforms: ["linux"]
url: "https://new.carta.tech/krlogin"
---

# krlogin(1)

remote login

## NAME

**rlogin** – remote login

## SYNOPSIS

*rlogin* \[**-8EKLdx**\] \[**-e** *char*\] \[**-k** *realm*\] \[**-l** *username*\] \[**-p** *portnumber*\] *host*

## DESCRIPTION

**Rlogin** starts a terminal session on a remote host *host*.

**Rlogin** first attempts to use the Kerberos authorization mechanism, described below. If the remote host does not supporting Kerberos the standard Berkeley *rhosts* authorization mechanism is used. The options are as follows:

- **-8**

  The **-8** option allows an eight-bit input data path at all times; otherwise parity bits are stripped except when the remote side's stop and start characters are other than ^S/^Q .

- **-E**

  The **-E** option stops any character from being recognized as an escape character. When used with the **-8** option, this provides a completely transparent connection.

- **-K**

  The **-K** option turns off all Kerberos authentication.

- **-L**

  The **-L** option allows the rlogin session to be run in \`\`litout'' (see [tty(4)](/tty/4.md)) mode.

- **-d**

  The **-d** option turns on socket debugging (see [setsockopt(2)](/setsockopt/2.md)) on the TCP sockets used for communication with the remote host.

- **-e**

  The **-e** option allows user specification of the escape character, which is \`\`~'' by default. This specification may be as a literal character, or as an octal value in the form \\nnn.

- **-k**

  The **-k** option requests rlogin to obtain tickets for the remote host in realm *realm* instead of the remote host's realm as determined by [krb\_realmofhost(3)](/krb_realmofhost/3.md).

- **-x**

  The **-x** option turns on DES encryption for all data passed via the rlogin session. This may impact response time and CPU utilization, but provides increased security.

- **-D**

  Use the TCP nodelay option (see [setsockopt(2)](/setsockopt/2.md)).

- **-p** **-portnumber**

  Specifies the port number to connect to on the remote host.

A line of the form \`\`\<escape char\>.'' disconnects from the remote host. Similarly, the line \`\`\<escape char\>^Z'' will suspend the **rlogin** session, and \`\`\<escape char\>\<delayed-suspend char\>'' suspends the send portion of the rlogin, but allows output from the remote system. By default, the tilde (\`\`~'') character is the escape character, and normally control-Y (\`\`^Y'') is the delayed-suspend character.

All echoing takes place at the remote site, so that (except for delays) the **rlogin** is transparent. Flow control via ^S/^Q and flushing of input and output on interrupts are handled properly.

## KERBEROS AUTHENTICATION

Each user may have a private authorization list in the file *.klogin* in their home directory. Each line in this file should contain a Kerberos principal name of the form *principal.instance@realm*. If the originating user is authenticated to one of the principals named in *.klogin*, access is granted to the account. The principal *accountname.@localrealm* is granted access if there is no *.klogin* file. Otherwise a login and password will be prompted for on the remote machine as in [login(1)](/login/1.md). To avoid certain security problems, the *.klogin* file must be owned by the remote user.

If Kerberos authentication fails, a warning message is printed and the standard Berkeley **rlogin** is used instead.

## ENVIRONMENT

The following environment variable is utilized by **rlogin**:

- TERM

  Determines the user's terminal type.

## SEE ALSO

[rsh(1)](/rsh/1.md), [kerberos(3)](/kerberos/3.md), [krb\_realmofhost(3)](/krb_realmofhost/3.md), [krb\_sendauth(3)](/krb_sendauth/3.md)

## HISTORY

The **rlogin** command appeared in 4.2BSD.

## BUGS

**Rlogin** will be replaced by [telnet(1)](/telnet/1.md) in the near future.

More of the environment should be propagated.