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Since updating to Yosemite, ssh from my Mac to a DNS alias takes about 7-8 seconds.

I've observed the following on multiple Macs running Yosemite. Assume I have a host name alpha, and a DNS alias to it named aa. The OS of the target doesn't matter.

1. ssh to an unqualified host name alias (CNAME record in DNS), e.g. ssh aa, takes about 7-8 seconds to connect
2. immediately repeating the same ssh command, ssh aa, connects in the "normal" amount of time (< 1s)
3. ssh to a fully qualified host name alias, e.g. ssh aa.example.com, connects in the normal amount of time
4. ssh to a regular host name (A record in DNS), e.g. ssh alpha.example.com, whether qualified or unqualified, connects in the normal amount of time.

When using ssh -vvv, the total delay is in one place:

$ ssh -vv **aa**
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug2: ssh_connect: needpriv 0
    *delay of 7-8 seconds*
debug1: Connecting to **aa** [10.10.1.2] port 22.
debug1: Connection established.
...

There is no difference in output between any of the 4 scenarios, except for the host name displayed.

This has happened on every release of Yosemite to the current version 10.10.3.

I have searched the web many times, and not found a single reference to this problem. Ideas?

Since updating to Yosemite, ssh from my Mac to a DNS alias takes about 7-8 seconds.

I've observed the following on multiple Macs running Yosemite. Assume I have a host name alpha, and a DNS alias to it named aa. The OS of the target doesn't matter.

1. ssh to an unqualified host name alias (CNAME record in DNS), e.g. ssh aa, takes about 7-8 seconds to connect
2. immediately repeating the same ssh command, ssh aa, connects in the "normal" amount of time (< 1s)
3. ssh to a fully qualified host name alias, e.g. ssh aa.example.com, connects in the normal amount of time
4. ssh to a regular host name (A record in DNS), e.g. ssh alpha.example.com, whether qualified or unqualified, connects in the normal amount of time.

When using ssh -vvv, the total delay is in one place:

$ ssh -vv aa
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug2: ssh_connect: needpriv 0
    *delay of 7-8 seconds*
debug1: Connecting to aa [10.10.1.2] port 22.
debug1: Connection established.
...

There is no difference in output between any of the 4 scenarios, except for the host name displayed.

This has happened on every release of Yosemite to the current version 10.10.3.

I have searched the web many times, and not found a single reference to this problem. Ideas?

Since updating to Yosemite, ssh from my Mac to a DNS alias takes about 7-8 seconds. I've observed the following on multiple Macs running Yosemite. Assume I have a host name alpha, and a DNS alias to it named aa. The OS of the target doesn't matter.

1. ssh to an unqualified host name alias (CNAME record in DNS), e.g. ssh aa, takes about 7-8 seconds to connect
2. immediately repeating the same ssh command, ssh aa, connects in the "normal" amount of time (< 1s)
3. ssh to a fully qualified host name alias, e.g. ssh aa.example.com, connects in the normal amount of time
4. ssh to a regular host name (A record in DNS), e.g. ssh alpha.example.com, rather qualified or unqualified, connects in the normal amount of time.

When using ssh -vvv, the total delay is in one place:

$ ssh -vv **aa**
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug2: ssh_connect: needpriv 0
    *delay of 7-8 seconds*
debug1: Connecting to **aa** [10.10.1.2] port 22.
debug1: Connection established.
...

There is no difference in output between any of the 4 scenarios, except for the host name displayed.

This has happened on every release of Yosemite to the current version 10.10.3.

I have searched the web many times, and not found a single reference to this problem. Ideas?

Since updating to Yosemite, ssh from my Mac to a DNS alias takes about 7-8 seconds.

I've observed the following on multiple Macs running Yosemite. Assume I have a host name alpha, and a DNS alias to it named aa. The OS of the target doesn't matter.

1. ssh to an unqualified host name alias (CNAME record in DNS), e.g. ssh aa, takes about 7-8 seconds to connect
2. immediately repeating the same ssh command, ssh aa, connects in the "normal" amount of time (< 1s)
3. ssh to a fully qualified host name alias, e.g. ssh aa.example.com, connects in the normal amount of time
4. ssh to a regular host name (A record in DNS), e.g. ssh alpha.example.com, whether qualified or unqualified, connects in the normal amount of time.

When using ssh -vvv, the total delay is in one place:

$ ssh -vv **aa**
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug2: ssh_connect: needpriv 0
    *delay of 7-8 seconds*
debug1: Connecting to **aa** [10.10.1.2] port 22.
debug1: Connection established.
...

There is no difference in output between any of the 4 scenarios, except for the host name displayed.

This has happened on every release of Yosemite to the current version 10.10.3.

I have searched the web many times, and not found a single reference to this problem. Ideas?