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SMB Login failure 3x weight measured

SMB Login. host unreachable (network routing broken)

SMB operation failed: [Errno 113] Host is unreachable
Events
873
Pts per check
4.2
Pts missed
3,637.5
Teams hit
8/13

Authority mappings

Which work roles, knowledge units, and EWU courses this error pattern touches. Hover for context, click to drill in.

DCWF roles: CE-463 Host Analyst CS-462 Control Systems Security Specialist CS-521 Cyber Defense Infrastructure Support Specialist CS-531 Cyber Defense Incident Responder IT-411 Technical Support Specialist IT-451 System Administrator
Knowledge Units: CD-ISC IT Systems Components CD-NDF Network Defense CD-OSA Operating Systems Administration CD-OSC Operating Systems Concepts CD-OSH Operating Systems Hardening
EWU courses: CSCD240-S26 CSCD210 CSCD212 CSCD240 CSCD327 CSCD379 CSCD380 CSCD381 CSCD434 CSCD470 CSCD496

What the message means

Errno 113 is 'No route to host'. Unlike 'connection refused' (the host is there but nothing is listening), 'unreachable' means the packet can't even reach the host. This is typically **routing or NAT broken**, not a Samba problem.

Why the service is down

Commands in order

  1. 1. 1. From the router, ping the server
    /ping <server-IP> count=3
    Expect
    3 replies
    Interpret and next
    Timeout = server is off, wrong IP, or L2 problem. Investigate the VM next.
  2. 2. 2. From the server, check your own IP
    ip addr
    Expect
    The IP you expect matches the IP in the router's NAT rule
    Interpret and next
    If server IP differs: either fix the NAT rule, or fix the server's netplan/interfaces.
  3. 3. 3. Any IP conflicts?
    arping -c 3 -I <iface> <your-IP> # from a second host in the same L2
    Expect
    1 distinct MAC address responds (yours)
    Interpret and next
    Multiple MACs = IP conflict. Either shut down the other host or change your IP + NAT rule.
  4. 4. 4. VM interface up?
    ip link show
    Expect
    <iface> state UP
    Interpret and next
    DOWN = `ip link set <iface> up`; check netplan.

Decision tree

Answer each question to route to the right fix.

Q: Can router ping the server?
Yes: Server is reachable. recheck SMB service status (see SMB Errno 111 playbook).
No:
Q: Is the VM powered on?
Yes: Wrong IP in NAT rule OR L2 broken. Reconcile IPs.
No: Boot the VM.

External references

Other patterns on this service