How ConfD processes capability exchange?

When I send “urn:ietf:params:netconf:base:1.1” to ConfD NETCONF server, I found ConfD was stuck in capability exchange. Generally (without “base:1.1”), I could see the following log in confd_netconf.log, but I didn’t see that when I use “base:1.1”. So I am wondering how ConfD processes capability exchange in hello messages? Is there any logs from ConfD I could use to see what happened in ConfD during capability exchange?

netconf id=20 got rpc: {urn:ietf:params:xml:ns:netconf:base:1.0}get attrs: message-id="1"

This should work just fine. For example, if I run the 1-2-3 example and give the command:

$ netconf-console --version=1.1 --get-config -x /dhcp

I get:

**> sess:30 new session

25-May-2017::18:55:26.519 **< sess:30 write:
<hello xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <capabilities>
    <capability>urn:ietf:params:netconf:base:1.0</capability>
    <capability>urn:ietf:params:netconf:base:1.1</capability>
    <capability>urn:ietf:params:netconf:capability:writable-running:1.0</capability>
    <capability>urn:ietf:params:netconf:capability:xpath:1.0</capability>
    <capability>urn:ietf:params:netconf:capability:validate:1.0</capability>
    <capability>urn:ietf:params:netconf:capability:validate:1.1</capability>
    <capability>urn:ietf:params:netconf:capability:rollback-on-error:1.0</capability>
    <capability>urn:ietf:params:netconf:capability:with-defaults:1.0?basic-mode=explicit&also-supported=report-all-tagged</capability>
    <capability>urn:ietf:params:netconf:capability:yang-library:1.0?revision=2016-06-21&module-set-id=5d61613c8653987798f271b2a9876561</capability>
    <capability>http://tail-f.com/ns/netconf/actions/1.0</capability>
    <capability>http://tail-f.com/ns/netconf/extensions</capability>
    <capability>http://tail-f.com/ns/aaa/1.1?module=tailf-aaa&revision=2015-06-16</capability>
    <capability>http://tail-f.com/ns/example/dhcpd?module=dhcpd</capability>
    <capability>http://tail-f.com/ns/kicker?module=tailf-kicker&revision=2017-03-16</capability>
    <capability>http://tail-f.com/ns/webui?module=tailf-webui&revision=2013-03-07</capability>
    <capability>http://tail-f.com/yang/acm?module=tailf-acm&revision=2013-03-07</capability>
    <capability>http://tail-f.com/yang/common-monitoring?module=tailf-common-monitoring&revision=2013-06-14</capability>
    <capability>http://tail-f.com/yang/confd-monitoring?module=tailf-confd-monitoring&revision=2013-06-14</capability>
    <capability>http://tail-f.com/yang/netconf-monitoring?module=tailf-netconf-monitoring&revision=2016-11-24</capability>
    <capability>urn:ietf:params:xml:ns:yang:iana-crypt-hash?module=iana-crypt-hash&revision=2014-08-06&features=crypt-hash-sha-512,crypt-hash-sha-256,crypt-hash-md5</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-inet-types?module=ietf-inet-types&revision=2013-07-15</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-netconf-acm?module=ietf-netconf-acm&revision=2012-02-22</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-netconf-monitoring?module=ietf-netconf-monitoring&revision=2010-10-04</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-netconf-notifications?module=ietf-netconf-notifications&revision=2012-02-06</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-restconf-monitoring?module=ietf-restconf-monitoring&revision=2016-08-15</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-yang-library?module=ietf-yang-library&revision=2016-06-21</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-yang-types?module=ietf-yang-types&revision=2013-07-15</capability>
    <capability>urn:ietf:params:xml:ns:netconf:base:1.0?module=ietf-netconf&revision=2011-06-01</capability>
    <capability>urn:ietf:params:xml:ns:yang:ietf-netconf-with-defaults?module=ietf-netconf-with-defaults&revision=2011-06-01</capability>
  </capabilities>
  <session-id>30</session-id>
</hello>

25-May-2017::18:55:26.549 **> sess:30 read:
<hello xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <capabilities>
    <capability>urn:ietf:params:netconf:base:1.1</capability>
  </capabilities>
</hello>

#209
<rpc message-id="1" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <get-config>
    <source>
      <running/>
    </source>
    <filter select=" /dhcp" type="xpath"
25-May-2017::18:55:26.558 **< sess:30 write:
/>
<rpc-reply message-id="1" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"  </get-config>
>
</rpc>
  <data>
    <dhcp xmlns="http://tail-f.com/ns/example/dhcpd">
      <SubNets>
        <subNet>
          <net>192.168.128.0</net>
          <mask>255.255.255.0</mask>
          <range>
            <lowAddr>192.168.128.60</lowAddr>
            <hiAddr>192.168.128.89</hiAddr>
          </range>
        </subNet>
      </SubNets>
    </dhcp>
  </data>
</rpc-reply>
]]>]]>
##

#147
<rpc message-id="0" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <close-session/>
</rpc>

25-May-2017::18:55:26.573 **< sess:30 write:
<rpc-reply message-id="0" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <ok/>
</rpc-reply>

**< sess:30 session closed

in the netconf.trace log.

For extra logging you can enable the error log or take a debug-dump, see the chapter on troubleshooting the the UG, but you have to send the logs to Tail-f support contact.