I noticed my node was not syncing, and through some debugging on #bitcoin-core-dev it seems like it was caused by running out of disk space which left the node in a desynced state, with the valid chain marked as invalid.

After freeing up some space and doing `reconsiderblock` it fixed it.

Comments from @sipa:

> Ugh. That is bad. Out of disk space should not result in database corruption.

> Database errors propagating up and being interpreted as (permanent) block invalidity was one of the contributing factors to the BDB/LevelDB fork in the 0.7/0.8 transition. 

logs:
```
2022-09-05T00:28:55Z UpdateTip: new best=000000000000000000087e337539b369b19570a88c493725020266387d22dac0 height=752167 version=0x2ce8e004 log2_work=93.70770
7 tx=761139817 date='2022-09-01T15:00:06Z' progress=0.998887 cache=146.8MiB(1101860txo)
2022-09-05T00:28:55Z Fatal LevelDB error: IO error: /home/jb55/.bitcoin/chainstate/2963623.ldb: No space left on device
2022-09-05T00:28:55Z You can use -debug=leveldb to get more complete diagnostic messages
2022-09-05T00:28:55Z *** System error while flushing: Fatal LevelDB error: IO error: /home/jb55/.bitcoin/chainstate/2963623.ldb: No space left on device
2022-09-05T00:28:55Z Error: A fatal internal error occurred, see debug.log for details
2022-09-05T00:28:56Z ERROR: ProcessNewBlock: ActivateBestChain failed (System error while flushing: Fatal LevelDB error: IO error: /home/jb55/.bitcoin/chains
tate/2963623.ldb: No space left on device)
2022-09-05T00:28:56Z ERROR: ConnectBlock: Consensus::CheckTxInputs: 221fa678c5c9953d6cd17e584f05c12ab10ba0f2fc8e8131e266f3f0e9819848, bad-txns-inputs-missing
orspent, CheckTxInputs: inputs missing/spent
2022-09-05T00:28:56Z InvalidChainFound: invalid block=000000000000000000079ba062298aa7cef1888f870c23e303a361c19b097ff8  height=752168  log2_work=93.707719  date=2022-09-01T15:13:42Z
2022-09-05T00:28:56Z InvalidChainFound:  current best=000000000000000000087e337539b369b19570a88c493725020266387d22dac0  height=752167  log2_work=93.707707  date=2022-09-01T15:00:06Z
2022-09-05T00:28:56Z ERROR: ConnectTip: ConnectBlock 000000000000000000079ba062298aa7cef1888f870c23e303a361c19b097ff8 failed, bad-txns-inputs-missingorspent, CheckTxInputs: inputs missing/spent
2022-09-05T00:28:56Z InvalidChainFound: invalid block=000000000000000000079ba062298aa7cef1888f870c23e303a361c19b097ff8  height=752168  log2_work=93.707719  date=2022-09-01T15:13:42Z
2022-09-05T00:28:56Z InvalidChainFound:  current best=000000000000000000087e337539b369b19570a88c493725020266387d22dac0  height=752167  log2_work=93.707707  date=2022-09-01T15:00:06Z
```

if (args.SoftSetBoolArg("-discover", false))
            LogPrintf("%s: parameter interaction: -externalip set -> setting -discover=0\n", __func__);
    }
    if (args.GetBoolArg("-blocksonly", DEFAULT_BLOCKSONLY)) {
        
        if (args.SoftSetBoolArg("-whitelistrelay", false))
            LogPrintf("%s: parameter interaction: -blocksonly=1 -> setting -whitelistrelay=0\n", __func__);
        
        if (args.SoftSetArg("-maxmempool", ToString(DEFAULT_BLOCKSONLY_MAX_MEMPOOL_SIZE_MB)))
            LogPrintf("%s: parameter interaction: -blocksonly=1 -> setting -maxmempool=%d\n", __func__, DEFAULT_BLOCKSONLY_MAX_MEMPOOL_SIZE_MB);
    }
    
    if (args.GetBoolArg("-whitelistforcerelay", DEFAULT_WHITELISTFORCERELAY)) {
        if (args.SoftSetBoolArg("-whitelistrelay", true))
            LogPrintf("%s: parameter interaction: -whitelistforcerelay=1 -> setting -whitelistrelay=1\n", __func__);
    }
    if (args.IsArgSet("-onlynet")) {
        const auto onlynets = args.GetArgs("-onlynet");
        bool clearnet_reachable = std::any_of(onlynets.begin(), onlynets.end(), [](const auto& net) {
            const auto n = ParseNetwork(net);
            return n == NET_IPV4 || n == NET_IPV6;
        });
        if (!clearnet_reachable && args.SoftSetBoolArg("-dnsseed", false)) {
            LogPrintf("%s: parameter interaction: -onlynet excludes IPv4 and IPv6 -> setting -dnsseed=0\n", __func__);
        }
    }
}
**
 * Initialize global loggers.