Re: Why does netstat not work in jails?

From: Allan Jude <allanjude_at_freebsd.org>
Date: Thu, 27 Aug 2015 22:33:04 -0400
On 2015-08-27 22:12, Julian Elischer wrote:
> On 8/28/15 9:54 AM, Chris H wrote:
>> I've been attempting to run jails on an 11-CURRENT
>> for the purpose of building world/kernel && ports
>> for all of our 9-STABLE production servers. I'm using
>> standard/classic jail setup(s) -- not using any
>> of the "convenience" ports/applications that abstract
>> the process in any way.
>> While everything seemed to go as intended/anticipated,
>> I'm seeing things I *didn't* expect.
>> The host network get's it's "public" IP from the router
>> in front of it. From the router, I insure that it is
>> allocated the same non-public IP everytime. So DHCP
>> assigns it 192.168.0.100. I assigned the jail 192.168.0.103.
>> SSHD is started within the jail, root IS allowed login.
>> But any attempt to ssh to 192.168.0.103 from the host,
>> returns:
>> ssh_exchange_identification: Connection closed by remote host.
>>
>> SSHD id NOT running on the host.
>>
>> inetd_flags="-wW -a 192.168.0.100" and syslogd_flags="-ss"
>> is set on the host via rc.conf
> what does netstat -aAn show (on the main host).
> 
>> second issue; loging into the jail, via jexex. If I perform:
>> netstat -nr
>> The following is returned:
>> netstat: kvm not available: /dev/mem: No such file or directory
> is there a /dev in the jail?  if you have set it up, have you allowed
> mem to be one of the exported devices?
> I forget the exact details on how to set this but hopefully it's a hint.
> I have to look it up every time.
> 
>> Routing tables
>> rt_tables: symbol not in namelist
>>
>> Any thought's jump out at anyone?
>>
>> Thanks!
>>
>> --Chris
>>
>> -- 

Normally I wouldn't think you would want /dev/mem to be accessible
inside a jail, but you can probably do it by editing some of the devfs
rules.

What info are you trying to get from netstat? some of the info is
available from sockstat etc.

-- 
Allan Jude


Received on Fri Aug 28 2015 - 00:32:38 UTC

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