VNX2 Networking & Connectivity Issues & Firmware Fixes

Networking & Connectivity Issues and Fixes for Dell EMC VNX Arrays

VNX5200, VNX5400, VNX5600, VNX5800, VNX7600 and VNX8000 arrays share the same Dell EMC VNX2 network stack. Typical symptoms such as iSCSI timeouts, Fibre Channel login loops and management‑port outages can interrupt host access or slow VMware datastores. Dell’s Operating‑Environment release notes document each connectivity bug and the exact firmware version that fixes it.

The table below consolidates those officially published networking fixes, listed from the most recent release to the earliest, so you can quickly check whether your array is already protected against link drops, port 443 conflicts, NTP drift and other traffic‑related faults before you plan an upgrade.

Software Updates for Networking Issues (Newest → Oldest)

Software Update Date Issue / Symptom
(verbatim from Dell Release Notes)		 Fix / Work‑around
VNX File OE 8.1.21.303 Aug 2022 Unable to store files scanned from HP MFP to CIFS share because SMB2 header request unsupported (Tracking 81133986 / SD‑1982). Protocol handler updated to accept valid SMB2 header fields.
VNX Block OE 05.33.009.5.217 Dec 2017
  • iSCSI data ports took 10–30 s to respond after discarded Task Abort, causing host‑side latency.
  • 16 Gbit FC login resource exhaustion → bug‑check 0x03B03024.
 Driver logic corrected for iSCSI abort handling; FC driver now frees login resources immediately.
VNX Block OE 05.33.009.5.184 Sep 2016 Management servers restarted because another process held port 443; cimomlog showed port in use. Port‑binding race removed; management service reclaims port 443 reliably.
VNX Block OE 05.33.009.5.155 Mar 2016
  • NTP time‑synchronization failures (Tracking 69259750 / 716725).
  • 16 Gbit FC port speed change AUTO↔16 G required manual link bounce.
 NTP client logic hardened; FC driver relogs ports automatically on speed change.
VNX Block OE 05.33.006.5.096 Mar 2015
  • IPv4 config failed when 4th octet = 255 and mask < /24 on iSCSI or mgmt ports.
  • Weekly iSCSI self‑test triggered false “Battery Not Ready” (logged here for cross‑ref).
 Address validation fixed; test schedule staggered.
VNX Block OE 05.33.008.5.119 Aug 2015 iSCSI packet storm on data ports could cause dual‑SP bug‑check 0x05900000 / 0x1E. Storm‑detection logic with throttling added to iSCSI stack.
VNX Block OE 05.33.000.5.072 Jul 2014 Scheduled BBU checks falsely flagged healthy BBUs (host I/O temporarily paused). Self‑test schedule corrected to prevent overlap.
VNX Block OE 05.33.000.5.051 Feb 2014 Erroneous call‑home “BBU missing” alerts; management path congestion. Call‑home detection logic fixed.
VNX Block OE 05.33.000.5.038 Jan 2014 Weekly tests on SPA+SPB simultaneously triggered BBU self‑test cycles; I/O stalls observed. Introduced coordinated SPA/SPB test mechanism.

Best‑Practice Tips to Prevent Network Faults

  • Enable Jumbo Frames (MTU 9000) end‑to‑end for iSCSI to reduce fragmentation.
  • Disable TCP Delayed ACK on ESXi iSCSI initiators to avoid latency spikes.
  • Pin FC Port Speed if hosts don’t auto‑negotiate 16 Gb correctly.
  • Configure two NTP servers; drift beyond ±5 min causes service‑processor warnings.

Additional References & Related Resources

Author

  • Phil Roussey

    Phil Roussey entered the computer-storage industry as an engineer in 1967. Over the next five decades he led product-management, supply-chain and technical-support teams responsible for mid-range and enterprise SAN/NAS arrays deployed worldwide. His experience spans tier-one OEMs and manufacturers such as Dell, EMC, HPE, NetApp, Samsung, Seagate, Hitachi, Western Digital, and many more. Phil has a Master's degree in Computer Science and remains active in the industry as a consultant on storage solution strategies, maintenance, & life-cycle management.