How To Fix Encryption/decryption Errors In Encryption/decryption Packets Slot 1 Authentication Failed Issues

Over the past few weeks, some users have encountered a known error message with an authentication failure when encrypting/decrypting slot 1 packets. This problem can occur for several reasons. Let’s get to know them below.

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Known Affected Versions

Description (partial)

Symptoms. The router displays an important error message:%VPN_HW-1-PACKET_ERROR: Location: 1 packet encryption/decryption error, outputAuthentication failed (0x20000000)This post does not contain enough information to properly troubleshoot and fixSituation. The error message should suggest source and destination IP addresses.Linked addresses with possible packet dump.Conditions: This indicator is seen on the router that offers the most VPN features.An environment that uses a hardware encryption accelerator.

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slot 1 packet encryption/decryption error output authentication error

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Nemeth Laszlocsirek every
Wednesday, November 26, 06:12:07 EST, 2008

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  • Hello everyone!I actually have 2 Cisco 7201 modems (c7200p-advipservicesk9-mz.124-15.T3.bin)with SA-VAM2+ VPN module.Between these modems I use an encrypted GRE tunnel:Interface tunnel0  Description TUNNEL  internet protocol address address IP MTU 1418 IP TCP configure mss 1300 IP ospf costs 100  Load interval 30  Save a couple 2  Tunnel source  Target tunnel encryption policy 10  3d ink  md5 hash  share approval in advance  Isacmp group 2Ingyombingyom Top Secret Crypto Address!cryptographic transform set ipsec nyulambulam-standard esp-3des esp-sha-hmacI have been receiving tracking error messages for the last 2-3 months y and only for countinghours (2-3 messages/minutes) per day, but only on one of the routers (onRouter availability approximately 9 weeks):Nov 25 03:06:49 PST: %VPN_HW-1-PACKET_ERROR: location: your packageESP encryption/decryption error, notepadLength: srcadr=, dstadr=, size=104, descriptor=0x7D4FNovember 26 PT: 03:07:34 %VPN_HW-1-PACKET_ERROR: Location: 5 packagesEncryption/decryption error, authentication exitError: srcadr=, dstadr=, size=160, handle=0x7D4FNov 26 03:07:34 PST: decrypt: %crypto-4-recvd_pkt_mac_err: check computerconnection failed id=11551 local= remote= router number=000008A5Those on the other side didn't record anything.The tunnel is down when I encounter this error.Idea?ThanksLaszlo

    slot 1 packet encryption/decryption error output authentication error

    Kian Jones