tree 1ba6ddc754a7d006a1bc034b6a5a7ebc16c7744b
parent e3a0217d4a84c185bb5011cfccc8860350294523
author David Greenaway <dgreenaway@google.com> 1562112727 +1000
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> 1562118518 +0000

Increase SSH timeout from 1 second to 10 seconds.

SSH is currently configured to automatically close the connection if
the peer has not been seen for 1 second. In particular, a keep alive
packet is sent from the client to server every second. If the client
doesn't see a response, it will close the connection.

Unfortunately, when the system comes under heavy network/CPU load, we
occasionally see spurious SSH disconnects. A high priority thread
spinning on a CPU for 2 seconds will disconnect all SSH sessions, for
example.

This CL increases the timeout from 1 second to 10 seconds on the client
side (i.e., a workstation SSH'ing into a Zircon system won't disconnect
until it hasn't heard from its peer for 10 seconds); and increases the
timeout from 5 seconds to 10 seconds on the server side (i.e., a Zircon
system's sshd won't disconnect a client for 10 seconds).

Users may observe their SSH clients not closing as quickly during
server reboots, sshd crashes, etc.

Bug: ZX-4414
Change-Id: I3e66ad658221ce6e688bb59e999f3750d730b18f