Unable to access ec2 ebs backed instance

For some unknown reason, an instance that was accessible via ssh on port 22 is no longer allowing access. After checking security groups and NACLs, correct routing tables associated with Gateways in the VPIC, and, rebooting the instance, We got a readout of the system logs but nothing seems to be alarming after comparing the logs with an instance that is healthy. The logs are as follows:

[ 0.000000] Linux version 4.9.76-3.78.amzn1.x86_64 (mockbuild@gobi-build-60009) (gcc version 7.2.1 20170915 (Red Hat 7.2.1-2) (GCC) ) #1 SMP Fri Jan 12 19:51:35 UTC 2018 [ 0.000000] Command line: root=LABEL=/ console=tty1 console=ttyS0 selinux=0 nvme_core.io_timeout=4294967295 [ 0.000000] x86/fpu: Supporting XSAVE feature 0x001: 'x87 floating point registers' [ 0.000000] x86/fpu: Supporting XSAVE feature 0x002: 'SSE registers' [ 0.000000] x86/fpu: Supporting XSAVE feature 0x004: 'AVX registers' [ 0.000000] x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256 [ 0.000000] x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'standard' format. [ 0.000000] x86/fpu: Using 'eager' FPU context switches. [ 0.000000] e820: BIOS-provided physical RAM map: [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009dfff] usable [ 0.000000] BIOS-e820: [mem 0x000000000009e000-0x000000000009ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000000e0000-0x00000000000fffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x00000000efffffff] usable [ 0.000000] BIOS-e820: [mem 0x00000000fc000000-0x00000000ffffffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000020fffffff] usable [ 0.000000] NX (Execute Disable) protection: active [ 0.000000] SMBIOS 2.7 present. [ 0.000000] Hypervisor detected: Xen [ 0.000000] Xen version 4.2. [ 0.000000] Netfront and the Xen platform PCI driver have been compiled for this kernel: unplug emulated NICs. [ 0.000000] Blkfront and the Xen platform PCI driver have been compiled for this kernel: unplug emulated disks. [ 0.000000] You might have to change the root device [ 0.000000] from /dev/hd[a-d] to /dev/xvd[a-d] [ 0.000000] in your root= kernel command line option [ 0.000000] e820: last_pfn = 0x210000 max_arch_pfn = 0x400000000 [ 0.000000] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WC UC- WT
[ 0.000000] e820: last_pfn = 0xf0000 max_arch_pfn = 0x400000000 [ 0.000000] found SMP MP-table at [mem 0x000fbc20-0x000fbc2f] mapped at [ffff8800000fbc20] [ 0.000000] RAMDISK: [mem 0x371e1000-0x37feffff] [ 0.000000] ACPI: Early table checksum verification disabled [ 0.000000] ACPI: RSDP 0x00000000000EA020 000024 (v02 Xen ) [ 0.000000] ACPI: XSDT 0x00000000FC00DDC0 000054 (v01 Xen HVM 00000000 HVML 00000000) [ 0.000000] ACPI: FACP 0x00000000FC00DA80 0000F4 (v04 Xen HVM 00000000 HVML 00000000) [ 0.000000] ACPI: DSDT 0x00000000FC001CE0 00BD19 (v02 Xen HVM 00000000 INTL 20090123) [ 0.000000] ACPI: FACS 0x00000000FC001CA0 000040 [ 0.000000] ACPI: FACS 0x00000000FC001CA0 000040 [ 0.000000] ACPI: APIC 0x00000000FC00DB80 0000D8 (v02 Xen HVM 00000000 HVML 00000000) [ 0.000000] ACPI: HPET 0x00000000FC00DCD0 000038 (v01 Xen HVM 00000000 HVML 00000000) [ 0.000000] ACPI: WAET 0x00000000FC00DD10 000028 (v01 Xen HVM 00000000 HVML 00000000) [ 0.000000] ACPI: SSDT 0x00000000FC00DD40 000031 (v02 Xen HVM 00000000 INTL 20090123) [ 0.000000] ACPI: SSDT 0x00000000FC00DD80 000031 (v02 Xen HVM 00000000 INTL 20090123) [ 0.000000] No NUMA configuration found [ 0.000000] Faking a node at [mem 0x0000000000000000-0x000000020fffffff] [ 0.000000] NODE_DATA(0) allocated [mem 0x20ffd9000-0x20fffafff] [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x0000000000001000-0x0000000000ffffff] [ 0.000000] DMA32 [mem 0x0000000001000000-0x00000000ffffffff] [ 0.000000] Normal [mem 0x0000000100000000-0x000000020fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000000001000-0x000000000009dfff] [ 0.000000] node 0: [mem 0x0000000000100000-0x00000000efffffff] [ 0.000000] node 0: [mem 0x0000000100000000-0x000000020fffffff] [ 0.000000] Initmem setup node 0 [mem 0x0000000000001000-0x000000020fffffff] [ 0.000000] ACPI: PM-Timer IO Port: 0xb008 [ 0.000000] IOAPIC[0]: apic_id 1, version 17, address 0xfec00000, GSI 0-47 [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 low level) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 low level) [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 low level) [ 0.000000] Using ACPI (MADT) for SMP configuration information [ 0.000000] ACPI: HPET id: 0x8086a201 base: 0xfed00000 [ 0.000000] smpboot: Allowing 15 CPUs, 13 hotplug CPUs [ 0.000000] PM: Registered nosave memory: [mem 0x00000000-0x00000fff] [ 0.000000] PM: Registered nosave memory: [mem 0x0009e000-0x0009ffff] [ 0.000000] PM: Registered nosave memory: [mem 0x000a0000-0x000dffff] [ 0.000000] PM: Registered nosave memory: [mem 0x000e0000-0x000fffff] [ 0.000000] PM: Registered nosave memory: [mem 0xf0000000-0xfbffffff] [ 0.000000] PM: Registered nosave memory: [mem 0xfc000000-0xffffffff] [ 0.000000] e820: [mem 0xf0000000-0xfbffffff] available for PCI devices [ 0.000000] Booting paravirtualized kernel on Xen HVM [ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645519600211568 ns [ 0.000000] setup_percpu: NR_CPUS:128 nr_cpumask_bits:128 nr_cpu_ids:15 nr_node_ids:1 [ 0.000000] percpu: Embedded 35 pages/cpu @ffff880207200000 s103448 r8192 d31720 u262144 [ 0.000000] PV qspinlock hash table entries: 256 (order: 0, 4096 bytes) [ 0.000000] Built 1 zonelists in Node order, mobility grouping on. Total pages: 2064264 [ 0.000000] Policy zone: Normal [ 0.000000] Kernel command line: root=LABEL=/ console=tty1 console=ttyS0 selinux=0 nvme_core.io_timeout=4294967295 [ 0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes) [ 0.000000] Memory: 8158532K/8388212K available (5494K kernel code, 1137K rwdata, 2472K rodata, 1280K init, 3132K bss, 229680K reserved, 0K cma-reserved) [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=15, Nodes=1 [ 0.000000] Kernel/User page tables isolation: enabled [ 0.000000] Hierarchical RCU implementation. [ 0.000000] Build-time adjustment of leaf fanout to 64. [ 0.000000] RCU restricting CPUs from NR_CPUS=128 to nr_cpu_ids=15. [ 0.000000] RCU: Adjusting geometry for rcu_fanout_leaf=64, nr_cpu_ids=15 [ 0.000000] NR_IRQS:8448 nr_irqs:952 16 [ 0.000000] xen:events: Using 2-level ABI [ 0.000000] xen:events: Xen HVM callback vector for event delivery is enabled [ 0.000000] Console: colour VGA+ 80x25 [ 0.000000] console [tty1] enabled [ 0.000000] Cannot get hvm parameter CONSOLE_EVTCHN (18): -22! [ 0.000000] console [ttyS0] enabled [ 0.000000] clocksource: hpet: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 30580167144 ns [ 0.000000] tsc: Fast TSC calibration using PIT [ 0.000000] tsc: Detected 2400.223 MHz processor [ 0.028000] Calibrating delay loop (skipped), value calculated using timer frequency.. 4800.17 BogoMIPS (lpj=9600352) [ 0.030140] pid_max: default: 32768 minimum: 301 [ 0.032019] ACPI: Core revision 20160831 [ 0.041796] ACPI: 3 ACPI AML tables successfully acquired and loaded [ 0.044026] Security Framework initialized [ 0.048404] Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes) [ 0.053333] Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes) [ 0.056592] Mount-cache hash table entries: 16384 (order: 5, 131072 bytes) [ 0.060009] Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes) [ 0.068263] CPU: Physical Processor ID: 0 [ 0.072003] CPU: Processor Core ID: 0 [ 0.076015] mce: CPU supports 2 MCE banks [ 0.078692] Last level iTLB entries: 4KB 1024, 2MB 1024, 4MB 1024 [ 0.080004] Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 1024, 1GB 4 [ 0.084003] Spectre V2 mitigation: Mitigation: Full generic retpoline [ 0.089093] Freeing SMP alternatives memory: 24K [ 0.098519] ftrace: allocating 21933 entries in 86 pages [ 0.128101] smpboot: Max logical packages: 8 [ 0.132105] x2apic: IRQ remapping doesn't support X2APIC mode [ 0.136006] Switched APIC routing to physical flat. [ 0.140000] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=0 pin2=0 [ 0.185139] clocksource: xen: mask: 0xffffffffffffffff max_cycles: 0x1cd42e4dffb, max_idle_ns: 881590591483 ns [ 0.192015] installing Xen timer for CPU 0 [ 0.196081] smpboot: CPU0: Intel(R) Xeon(R) CPU E5-2676 v3 @ 2.40GHz (family: 0x6, model: 0x3f, stepping: 0x2) [ 0.201560] cpu 0 spinlock event irq 53 [ 0.204007] Performance Events: unsupported p6 CPU model 63 no PMU driver, software events only. [ 0.208609] installing Xen timer for CPU 1 [ 0.211388] x86: Booting SMP configuration: [ 0.212007] .... node #0, CPUs: #1[ 0.216030] cpu 1 spinlock event irq 59 [ 0.219275] x86: Booted up 1 node, 2 CPUs [ 0.220007] smpboot: Total of 2 processors activated (9600.35 BogoMIPS) [ 0.224454] devtmpfs: initialized [ 0.224454] x86/mm: Memory block size: 128MB [ 0.232069] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns [ 0.236021] futex hash table entries: 4096 (order: 6, 262144 bytes) [ 0.240060] NET: Registered protocol family 16 [ 0.260012] cpuidle: using governor ladder [ 0.280006] cpuidle: using governor menu [ 0.282648] ACPI: bus type PCI registered [ 0.284009] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5 [ 0.288310] PCI: Using configuration type 1 for base access [ 0.308134] HugeTLB registered 2 MB page size, pre-allocated 0 pages [ 0.312093] ACPI: Added _OSI(Module Device) [ 0.314822] ACPI: Added _OSI(Processor Device) [ 0.316012] ACPI: Added _OSI(3.0 _SCP Extensions) [ 0.318974] ACPI: Added _OSI(Processor Aggregator Device) [ 0.323569] ACPI: Interpreter enabled [ 0.324017] ACPI: (supports S0 S4 S5) [ 0.326449] ACPI: Using IOAPIC for interrupt routing [ 0.328035] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug [ 0.348482] random: fast init done [ 0.376873] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff]) [ 0.380016] acpi PNP0A03:00: _OSC: OS supports [Segments MSI] [ 0.383750] acpi PNP0A03:00: _OSC failed (AE_NOT_FOUND); disabling ASPM [ 0.384018] acpi PNP0A03:00: fail to add MMCONFIG information, can't access extended PCI configuration space under this bridge. [ 0.389126] acpiphp: Slot [0] registered [ 0.392498] acpiphp: Slot [3] registered [ 0.395603] acpiphp: Slot [4] registered [ 0.396308] acpiphp: Slot [5] registered [ 0.399438] acpiphp: Slot [6] registered [ 0.400355] acpiphp: Slot [7] registered [ 0.403342] acpiphp: Slot [8] registered [ 0.404277] acpiphp: Slot [9] registered [ 0.407008] acpiphp: Slot [10] registered [ 0.408279] acpiphp: Slot [11] registered [ 0.411141] acpiphp: Slot [12] registered [ 0.412286] acpiphp: Slot [13] registered [ 0.415130] acpiphp: Slot [14] registered [ 0.416290] acpiphp: Slot [15] registered [ 0.419209] acpiphp: Slot [16] registered [ 0.420278] acpiphp: Slot [17] registered [ 0.423298] acpiphp: Slot [18] registered [ 0.424268] acpiphp: Slot [19] registered [ 0.427590] acpiphp: Slot [20] registered [ 0.428328] acpiphp: Slot [21] registered [ 0.432274] acpiphp: Slot [22] registered [ 0.435300] acpiphp: Slot [23] registered [ 0.436284] acpiphp: Slot [24] registered [ 0.439219] acpiphp: Slot [25] registered [ 0.440285] acpiphp: Slot [26] registered [ 0.443182] acpiphp: Slot [27] registered [ 0.444291] acpiphp: Slot [28] registered [ 0.447217] acpiphp: Slot [29] registered [ 0.448415] acpiphp: Slot [30] registered [ 0.451265] acpiphp: Slot [31] registered [ 0.452277] PCI host bridge to bus 0000:00 [ 0.455088] pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window] [ 0.456006] pci_bus 0000:00: root bus resource [io 0x0d00-0xffff window] [ 0.460008] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window] [ 0.464007] pci_bus 0000:00: root bus resource [mem 0xf0000000-0xfbffffff window] [ 0.468008] pci_bus 0000:00: root bus resource [bus 00-ff] [ 0.476922] pci 0000:00:01.1: legacy IDE quirk: reg 0x10: [io 0x01f0-0x01f7] [ 0.480006] pci 0000:00:01.1: legacy IDE quirk: reg 0x14: [io 0x03f6] [ 0.484007] pci 0000:00:01.1: legacy IDE quirk: reg 0x18: [io 0x0170-0x0177] [ 0.488008] pci 0000:00:01.1: legacy IDE quirk: reg 0x1c: [io 0x0376] [ 0.492882] * Found PM-Timer Bug on the chipset. Due to workarounds for a bug, [ 0.492882] * this clock source is slow. Consider trying other clock sources [ 0.497209] pci 0000:00:01.3: quirk: [io 0xb000-0xb03f] claimed by PIIX4 ACPI [ 0.506334] ACPI: PCI Interrupt Link [LNKA] (IRQs *5 10 11) [ 0.511381] ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11) [ 0.515186] ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11) [ 0.519047] ACPI: PCI Interrupt Link [LNKD] (IRQs *5 10 11) [ 0.539555] ACPI: Enabled 2 GPEs in block 00 to 0F [ 0.540081] xen:balloon: Initialising balloon driver [ 0.544080] vgaarb: setting as boot device: PCI:0000:00:02.0 [ 0.547559] vgaarb: device added: PCI:0000:00:02.0,decodes=io+mem,owns=io+mem,locks=none [ 0.552019] vgaarb: loaded [ 0.554173] vgaarb: bridge control possible 0000:00:02.0 [ 0.556063] PCI: Using ACPI for IRQ routing [ 0.560018] NetLabel: Initializing [ 0.564011] NetLabel: domain hash size = 128 [ 0.566806] NetLabel: protocols = UNLABELED CIPSOv4 [ 0.568018] NetLabel: unlabeled traffic allowed by default [ 0.571442] HPET: 3 timers in total, 0 timers will be used for per-cpu timer [ 0.576019] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0 [ 0.580004] hpet0: 3 comparators, 64-bit 62.500000 MHz counter [ 0.588020] clocksource: Switched to clocksource xen [ 0.598500] VFS: Disk quotas dquot_6.6.0 [ 0.601309] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes) [ 0.605672] pnp: PnP ACPI init [ 0.608218] system 00:00: [mem 0x00000000-0x0009ffff] could not be reserved [ 0.612470] system 00:01: [io 0x08a0-0x08a3] has been reserved [ 0.616097] system 00:01: [io 0x0cc0-0x0ccf] has been reserved [ 0.619622] system 00:01: [io 0x04d0-0x04d1] has been reserved [ 0.623416] system 00:07: [io 0x10c0-0x1141] has been reserved [ 0.626956] system 00:07: [io 0xb044-0xb047] has been reserved [ 0.647502] pnp: PnP ACPI: found 8 devices [ 0.656850] clocksource: acpi_pm: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 2085701024 ns [ 0.662917] NET: Registered protocol family 2 [ 0.666000] TCP established hash table entries: 65536 (order: 7, 524288 bytes) [ 0.670774] TCP bind hash table entries: 65536 (order: 8, 1048576 bytes) [ 0.674720] TCP: Hash tables configured (established 65536 bind 65536) [ 0.678934] UDP hash table entries: 4096 (order: 5, 131072 bytes) [ 0.682528] UDP-Lite hash table entries: 4096 (order: 5, 131072 bytes) [ 0.686312] NET: Registered protocol family 1 [ 0.689188] pci 0000:00:00.0: Limiting direct PCI/PCI transfers [ 0.692793] pci 0000:00:01.0: PIIX3: Enabling Passive Release [ 0.696602] pci 0000:00:01.0: Activating ISA DMA hang workarounds [ 0.700437] pci 0000:00:02.0: Video device with shadowed ROM at [mem 0x000c0000-0x000dffff] [ 0.705563] Unpacking initramfs... [ 0.917049] Freeing initrd memory: 14396K [ 0.919784] PCI-DMA: Using software bounce buffering for IO (SWIOTLB) [ 0.923539] software IO TLB [mem 0xec000000-0xf0000000] (64MB) mapped at [ffff8800ec000000-ffff8800efffffff] [ 0.929857] audit: initializing netlink subsys (disabled) [ 0.933233] audit: type=2000 audit(1518127712.303:1): initialized [ 0.937152] Initialise system trusted keyrings [ 0.939991] workingset: timestamp_bits=36 max_order=21 bucket_order=0 [ 0.981248] Key type asymmetric registered [ 0.984175] Asymmetric key parser 'x509' registered [ 0.987335] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 254) [ 0.992400] io scheduler noop registered (default) [ 0.995457] pci_hotplug: PCI Hot Plug PCI Core version: 0.5 [ 1.000341] pciehp: PCI Express Hot Plug Controller Driver version: 0.4 [ 1.006019] xen:grant_table: Grant tables using version 1 layout [ 1.009648] Grant table initialized [ 1.012106] Cannot get hvm parameter CONSOLE_EVTCHN (18): -22! [ 1.015979] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled [ 1.046059] 00:06: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A [ 1.051547] xen_netfront: Initialising Xen virtual ethernet driver [ 1.056102] i8042: PNP: PS/2 Controller [PNP0303:PS2K,PNP0f13:PS2M] at 0x60,0x64 irq 1,12 [ 1.065396] serio: i8042 KBD port at 0x60,0x64 irq 1 [ 1.068437] serio: i8042 AUX port at 0x60,0x64 irq 12 [ 1.071515] hidraw: raw HID events driver (C) Jiri Kosina [ 1.074748] Invalid max_queues (4), will use default max: 2. [ 1.079104] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input0 [ 1.079163] NET: Registered protocol family 17 [ 1.079382] microcode: sig=0x306f2, pf=0x1, revision=0x3b [ 1.084581] microcode: Microcode Update Driver: v2.01 <tigran@aivazian.fsnet.co.uk>, Peter Oruba [ 1.084705] registered taskstats version 1 [ 1.084708] Loading compiled-in X.509 certificates [ 1.086665] alg: No test for pkcs1pad(rsa,sha256) (pkcs1pad(rsa-generic,sha256)) [ 1.087335] Loaded X.509 cert 'Build time autogenerated kernel key: 90a8ce1f8c89128b6c9d51818805938ea4d0459c' [ 1.087870] zswap: default zpool zbud not available [ 1.087870] zswap: pool creation failed [ 1.089431] blkfront: xvda: barrier or flush: disabled; persistent grants: disabled; indirect descriptors: enabled; [ 1.093875] xvda: xvda1 [ 1.190151] Freeing unused kernel memory: 1280K [ 1.194519] Write protecting the kernel read-only data: 10240k [ 1.199910] Freeing unused kernel memory: 632K [ 1.207242] Freeing unused kernel memory: 1624K [ 1.225990] dm_mod: module verification failed: signature and/or required key missing - tainting kernel [ 1.235306] device-mapper: uevent: version 1.0.3 [ 1.239778] device-mapper: ioctl: 4.35.0-ioctl (2016-06-23) initialised: dm-devel@redhat.com [ 1.251244] udevd[840]: starting version 173 [ 1.286380] SCSI subsystem initialized [ 1.294718] scsi host0: ata_piix [ 1.305494] scsi host1: ata_piix [ 1.308485] ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc100 irq 14 [ 1.313133] ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc108 irq 15 growroot: NOCHANGE: disk=/dev/xvda partition=1: size=1073737694, it cannot be grown [ 1.530413] EXT4-fs (xvda1): INFO: recovery required on readonly filesystem [ 1.535346] EXT4-fs (xvda1): write access will be enabled during recovery [ 1.948112] tsc: Refined TSC clocksource calibration: 2400.002 MHz [ 1.952697] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x22983938a92, max_idle_ns: 440795216168 ns [ 2.818080] random: crng init done [ 3.027038] EXT4-fs (xvda1): orphan cleanup on readonly fs [ 3.035785] EXT4-fs (xvda1): 1 orphan inode deleted [ 3.039754] EXT4-fs (xvda1): recovery complete [ 3.047535] EXT4-fs (xvda1): mounted filesystem with ordered data mode. Opts: (null) [ 3.083990] dracut: Remounting /dev/disk/by-label/\x2f with -o noatime,ro [ 3.130440] EXT4-fs (xvda1): mounted filesystem with ordered data mode. Opts: (null) [ 3.139953] dracut: Mounted root filesystem /dev/xvda1 [ 3.166094] dracut: Switching root image_name="amzn-ami-hvm" image_version="2017.09" image_arch="x86_64" image_file="amzn-ami-hvm-2017.09.1.20180115-x86_64.ext4.gpt" image_stamp="eeb4-18f0" image_date="20180115184347" recipe_name="amzn ami" recipe_id="c9c871d2-7d71-8baa-e873-c70f-cbbe-ddb2-79ee86e7"

Is there something being missed that the logs highlight that are causing denial of ssh access on port 22?

@LloydMoore Since you are getting below logs in your system log

[    0.000000] You might have to change the root device
[    0.000000] from /dev/hd[a-d] to /dev/xvd[a-d]
[    0.000000] in your root= kernel command line option

You might need to detach and rename your root device to fix this issue.

Please follow below step's to fix this issue. Please check and suggest if this fixed your issues Before you start : This procedure requires a stop and start of the instance. Be aware of the following:

1. If your instance is part of an Amazon EC2 Auto Scaling group, then stopping the instance might terminate it. Instances launched with Amazon EMR, AWS CloudFormation, AWS Elastic Beanstalk might be part of an AWS Auto Scaling group. Instance termination in this scenario depends on the instance scale-in protection settings for your Auto Scaling group. If your instance is part of an Auto Scaling group, temporarily remove it from the Auto Scaling group before starting the resolution steps.

2. Stopping and starting the instance changes the public IP address of your instance. It's a best practice to use an Elastic IP address instead of a public IP address when routing external traffic to your instance.

3. To guard against the possibility of data loss, take a snapshot of your volume before attempting to unmount it. Forced detachment of a stuck volume can cause damage to the file system or the data it contains or an inability to attach a new volume using the same device name, unless you reboot the instance.

4. You must be a root user or need to have or atlease sudo privilege to follow this procedure.

Keep these things handy

1. --instance-id
2. --volume-id
3. --availability-zone

1 Firstly You have to create another instance, instance-B (EBS Backed) in the same availability zone as instance-A
2 Stop Instance
3 Detach the root EBS volume from instance-A
4 Attach that EBS volume to instance-B as /dev/xvdf
5 mount /dev/xvdf On instance-B use command: 
6 sudo mkdir -p /mnt/xvdf
7 sudo mount /dev/xvdf /mnt/xvdf
8 check public key, if you have the corresponding private key then it's good else create new key pair and add it to /mnt/xvdf/home/root/.ssh/authorized_keys(if not root user replace root with your current user profile ex: ec2-user)
9 compare /etc/fstab file of instance-B with /mnt/xvdf/etc/fstab and make necessary modifications's to /mnt/xvdf//etc/fstab file.
10 Unmount volume from instance-B : umount /mnt/xvdf
11 Attach volume back to instance-A as root
12 Restart instance-A

[https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-detaching-volume.html] [https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-attaching-volume.html] [https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-using-volumes.html] [https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/device_naming.html] [https://stackoverflow.com/a/22747744/3224357] https://forums.aws.amazon.com/thread.jspa?messageID=984907#984907 https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-using-volumes.html