FortiGate-51B
Fortinet FortiGate 51B — Fortinet FortiGate-51B next-generation firewall
Lifecycle position
Options from here
Keep it in production past the OEM cutoff with an independent maintainer.
Buy spares now, while units still circulate on the secondary market.
It is unsupported today — set a migration timeline and budget.
Low-criticality role — document the risk, harden backups, retire on your terms.
Other SKUs in FortiGate 51B
FortiGate-51B — questions
Is the Fortinet FortiGate-51B still supported?
No. Fortinet's last date of support for FortiGate-51B was Dec 2019 (per the Fortinet end-of-sale bulletin) — it is past end of service life.
When did the FortiGate-51B reach end of sale?
FortiGate-51B reached end of sale Dec 2014, per the Fortinet end-of-sale bulletin.
What is the last date of support (EOSL) for the FortiGate-51B?
Dec 2019 — per the Fortinet end-of-sale bulletin.
Can the FortiGate-51B be maintained after Fortinet support ends?
After the last date of support, FortiGate-51B units can often be kept in production through third-party maintenance providers. Fortinet no longer issues software fixes, support, or hardware replacement for it.