From a2c4c0cd3a2e5b58b36718290cb7c31f99f6495e Mon Sep 17 00:00:00 2001 From: Antonio Murdaca Date: Thu, 10 Dec 2015 08:58:02 +0100 Subject: [PATCH] api: client: info: print a warning if dm is using a loopback file Signed-off-by: Antonio Murdaca --- api/client/info.go | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/api/client/info.go b/api/client/info.go index 1abc20db2e..4b171720ab 100644 --- a/api/client/info.go +++ b/api/client/info.go @@ -30,7 +30,13 @@ func (cli *DockerCli) CmdInfo(args ...string) error { if info.DriverStatus != nil { for _, pair := range info.DriverStatus { fmt.Fprintf(cli.out, " %s: %s\n", pair[0], pair[1]) + + // print a warning if devicemapper is using a loopback file + if pair[0] == "Data loop file" { + fmt.Fprintf(cli.err, " WARNING: Usage of loopback devices is strongly discouraged for production use. Either use `--storage-opt dm.thinpooldev` or use `--storage-opt dm.no_warn_on_loop_devices=true` to suppress this warning.") + } } + } ioutils.FprintfIfNotEmpty(cli.out, "Execution Driver: %s\n", info.ExecutionDriver) ioutils.FprintfIfNotEmpty(cli.out, "Logging Driver: %s\n", info.LoggingDriver)