[fvt]2.12.1 switchdiscover -s snmp could not use port 161 by nmap way on rh env

[junxiawang]

env:rh
build:latest build lsdef - Version 2.12.1 (git commit 2794ca5, built Thu Jun 2 09:30:41 EDT 2016)
How to reproduce:

[root@c910f04x27v02 result]# switchdiscover  --range 10.5.24.1
Discovering switches using nmap for 10.5.24.1. It may take long time...
ip              name                    vendor                                              mac         
------------    ------------            ------------                                        ------------
10.5.24.1  [root@c910f04x27v02 result]# switchdiscover  --range 10.5.24.1 -s snmp
Discovering switches using snmpwalk.....
Could not process this command: /usr/bin/nmap -P0 -v -sU -p 161 -oA snmp_scan 10.5.24.1 | grep 'open port 161' 
 No switch found 
    switch-10-5-24-1        Juniper Networks                                    5C:5E:AB:64:CA:7F
--------------------------------------------->
Questions:
 1) I do not know why snmp discover using nmap way
 2) I do not think all env could use port 161

[cxhong]

1. we used nmap for snmp discover to better parse the ip range.
2. port 161 has to be open to allow snmpwalk command to communicate with switch

# snmpwalk -Os -v1 -c public 10.5.24.1 1.3.6.1.2.1.1.1
Timeout: No Response from 10.5.24.1

[junxiawang]

@cxhong but I could get the switch using nmap but not snmp
[root@c910f04x27v02 ~]# switchdiscover --range 10.5.24.1
Discovering switches using nmap for 10.5.24.1. It may take long time...
ip name vendor mac

---

10.5.24.1 switch-10-5-24-1 Juniper Networks 5C:5E:AB:64:CA:7F
[root@c910f04x27v02 ~]#

[cxhong]

switchdiscover command can't do anything if the device does not respond to SNMP queries for snmp based scan. Any snmp command we sent out will return "Timeout" messages if snmp server is not enabled.

[daniceexi]

@cxhong That's ok to skip the switch if the snmp port is not opened. But we should make the message to be more reasonable instead of following:

Could not process this command: /usr/bin/nmap -P0 -v -sU -p 161 -oA snmp_scan 10.5.24.1 | grep 'open port 161' 
 No switch found 

We may say: cannot find any device which enabled snmp port.

[cxhong]

Modified the message and will checked in PR #1244