3

According to Mapping Cisco CSR 1000v Network Interfaces to VM Network Interfaces document, the newer CSR 1000v routers no longer have the dedicated management interface Gi0:

In Cisco IOS XE Release 3.10S and earlier, the first vNIC added is automatically mapped to the
GigabitEthernet0 management interface. Allsubsequent vNICs added are mapped to router interfaces.Support
for the GigabitEthernet0 interface was removed in Cisco IOS XE Release 3.11S.

For example, my CSR 1000v running Cisco IOS XE version 16.07.01 no longer has the Gi0:

csr1000v#show platform software vnic-if interface-mapping
-------------------------------------------------------------
 Interface Name        Driver Name         Mac Addr
-------------------------------------------------------------
 GigabitEthernet3       net_virtio         5254.0072.7c89
 GigabitEthernet2       net_virtio         5254.0072.7c88
 GigabitEthernet1       net_virtio         5254.0072.7c81
-------------------------------------------------------------

csr1000v#
csr1000v#sh ip int bri
Interface              IP-Address      OK? Method Status                Protocol
GigabitEthernet1       192.168.11.1    YES NVRAM  up                    up
GigabitEthernet2       unassigned      YES NVRAM  administratively down down
GigabitEthernet3       unassigned      YES NVRAM  administratively down down
csr1000v#

Does the modern Cisco CSR 1000v have a management interface?

3

If it doesn't, you just can define one.

(pseudo config code, actual syntax may vary)

vrf definition MYMGMTVRF
 address-family ipv4
 exit-address-family

 address-family ipv6
 exit-address-family

! Pick one of your Interfaces to be the Management IF
interface GigabitM
 vrf forwardung MYMGMTVRF
 ip address ...
 ipv6 address ...

! add a (default) routes for the given Managament VRF
ip   route vrf MYMGMTVRF 0.0.0.0 0.0.0.0.0 GigabitM <nextHopIP>
ipv6 route vrf MYMGMTVRF ... 

Then make sure that you bind the various management related client or server instances to your management VRF or an interface which is attached to that VRF.

logging source interface GigabitM
logging host <SyslogServerIP> vrf MYMGMTVRF
ntp server vrf MYMGMTVRF <NTPServerIP>
ip ftp source-interface GigabitM
ip ssh source-interface GigabitM
....

Sometimes, mapping "workload things" like (sub)interfaces, routing protocol instances, IPSec endpoints etc. (in short: The things that actually forward traffic) into their own VRF is easier and more straightforward than getting all the management things properly VRF-mapped.

Therefore, deployment scenario permitting, you could just go ahead and map everything workload related into a "workload VRF" (multiple, if multiple customers) and the pertaining interfaces along with it, and leave only one of the CSR1Kv's Interfaces in the global routing table.

Then that remaining interface will implicetely become your management interface, and you won't have to go through all the trouble of (not) forgetting FTP client, HTTP client or even server, SSH client and server, NTP client, syslog, snmp trap source and trap receiver, TACACS+ and RADIUS clients...

Not forgetting them was one thing - IOS's capabilities to run management services in VRF aware mode weren't always what they are in contemporay IOS-XE.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.